Per unit price or other underlying value of transaction computed pursuant to Exchange Act Rule 0-11 (set forth the amount on which the filing
fee is calculated and state how it was determined):

(4)

Proposed maximum aggregate value of transaction:

(5)

Total fee paid:

☐

Fee paid previously with preliminary materials.

☐

Check box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement
number, or the Form or Schedule and the date of its filing.

On October 31, 2018, Encana Corporation, a Canadian corporation (Encana), Neapolitan Merger Corp., a Delaware corporation and
an indirect, wholly-owned subsidiary of Encana (Merger Sub), and Newfield Exploration Company, a Delaware corporation (Newfield), entered into an Agreement and Plan of Merger (the merger agreement), providing for
the merger of Merger Sub with and into Newfield, with Newfield surviving the merger as an indirect, wholly-owned subsidiary of Encana (the merger).

In connection with the merger, Encana will issue Encana common shares to stockholders of Newfield (the share issuance). Under the
rules of the New York Stock Exchange (the NYSE) and the Toronto Stock Exchange (the TSX), Encana is required to obtain Encana shareholder approval of the share issuance. Accordingly, Encana will hold a special meeting of
shareholders (the Encana special meeting) to vote on the share issuance (the share issuance proposal). At the Encana special meeting, Encana shareholders will also vote on a proposal to approve the adjournment of the Encana
special meeting, if necessary or appropriate, to solicit additional proxies if there are not sufficient votes to approve the share issuance proposal (the Encana adjournment proposal). Approval of each of these proposals requires the
affirmative vote of a majority of votes cast by Encana shareholders entitled to vote thereon and present in person or represented by proxy at the Encana special meeting.

The Encana special meeting will be held on February 12, 2019 at the Oddfellows Building, Ballroom (Floor 4), 100  6th Avenue S.W.,
Calgary, Alberta, at 8:00 a.m., Mountain Time. The Encana board of directors (the Encana board) unanimously recommends that Encana shareholders vote FOR the
share issuance proposal and FOR the Encana adjournment proposal.

In addition, under the
laws of the State of Delaware and pursuant to Newfields bylaws, Newfield is required to obtain Newfield stockholder approval of the adoption of the merger agreement and related matters as described in the attached joint proxy
statement/prospectus. Accordingly, Newfield will hold a special meeting of Newfield stockholders (the Newfield special meeting) to vote to adopt the merger agreement (the merger agreement proposal). Approval of the merger
agreement proposal requires the affirmative vote, in person or by proxy, of the holders of at least 662⁄3% of the issued and outstanding shares of Newfield common
stock entitled to vote thereon. At the Newfield special meeting, Newfield stockholders will also vote on proposals to approve (i) on an advisory (non-binding) basis, the compensation that may be paid or
become payable to Newfields named executive officers in connection with the merger (the non-binding compensation advisory proposal), which is not a condition to the merger, and (ii) the
adjournment of the Newfield special meeting, if necessary or appropriate, to solicit additional proxies if there are not sufficient votes to adopt the merger agreement (the Newfield adjournment proposal). Approval of each of the non-binding compensation advisory proposal and the Newfield adjournment proposal requires the affirmative vote of a majority of votes cast by Newfield stockholders entitled to vote thereon and present in person or
represented by proxy at the Newfield special meeting.

The Newfield special meeting will be held on February 12, 2019 at the Four Seasons
Hotel, Fairfield Ballroom, 1300 Lamar St., Houston, Texas 77010 at 9:00 a.m., Central Time. TheNewfield board of directors (the Newfield board) unanimously recommends that Newfield stockholders vote
FOR the merger agreement proposal, FOR the non-binding compensation advisory proposal and
FOR the Newfield adjournment proposal.

If the merger is completed, each issued and
outstanding share of Newfield common stock (with certain exceptions described in the accompanying joint proxy statement/prospectus) will convert into the right to receive 2.6719 Encana common shares with cash paid in lieu of the issuance of
fractional Encana common shares, if any. Although the number of Encana common shares that Newfield stockholders will receive is fixed, the market value of the merger consideration will fluctuate with the market price of Encana common shares and will
not be known at the time Newfield stockholders vote to adopt the merger agreement or at the time Encana shareholders vote to approve the share issuance. Based on the closing price of the Encana common shares on the NYSE on October 31, 2018, the
last trading day before the public announcement of the parties entering into the merger agreement, the 2.6719 exchange ratio represented approximately $27.36 in value for each share of Newfield common stock. Based on the closing price of the Encana
common shares on the NYSE on January 7, 2019, the last practicable trading day before the date of the joint proxy statement/prospectus accompanying this notice, the 2.6719 exchange ratio represented approximately $16.78 in value for each share of
Newfield common stock. Based upon the estimated number of Encana common shares and shares of Newfield common stock as well as the outstanding equity of the parties that will be outstanding immediately prior to the consummation of the merger, we
estimate that, upon consummation of the merger, existing Encana shareholders will hold approximately 63.5% and former Newfield stockholders will hold approximately 36.5% of the issued and outstanding Encana common shares. We urge you to obtain
current market quotations for Encana (trading symbol ECA) and Newfield (trading symbol NFX).

The obligations of
Encana and Newfield to complete the merger are subject to the satisfaction or waiver of a number of conditions set forth in the merger agreement, a copy of which is included as Annex A to the attached joint proxy statement/prospectus. The
attached joint proxy statement/prospectus describes the Encana special meeting, the Newfield special meeting, the merger, the documents and agreements related to the merger, the share issuance and other related matters. It also contains or
references information about Encana and Newfield and certain related agreements and matters. Please carefully read this entire joint proxy statement/prospectus, including Risk Factors, beginning on page 39,
for a discussion of the risks relating to the proposed merger. You also can obtain information about Encana and Newfield from documents that each has filed with the Securities and Exchange Commission.

Sincerely,

Douglas J. Suttles

President & Chief Executive Officer and Director

Encana Corporation

Lee K. Boothby

President, Chief Executive
Officer and Chairman

Newfield Exploration Company

Neither the Securities and Exchange Commission nor any state securities commission has approved or
disapproved of the securities to be issued in connection with the merger described in this joint proxy statement/prospectus or determined if this joint proxy statement/prospectus is accurate or complete. Any representation to the contrary is a
criminal offense.

This joint proxy statement/prospectus is dated January 8, 2019 and is first being mailed to Encana shareholders of
record and Newfield stockholders of record on or about January 8, 2019.

ENCANA CORPORATION

Suite 4400, 500 Centre Street S.E., P.O. Box 2850

Calgary, Alberta, Canada, T2P 2S5

NOTICE OF SPECIAL MEETING OF SHAREHOLDERS TO BE HELD ON FEBRUARY 12, 2019

This is a notice that a special meeting (the Encana special meeting) of shareholders (Encana shareholders) of Encana
Corporation, a Canadian corporation (Encana), will be held on February 12, 2019 at the Oddfellows Building, Ballroom (Floor 4), 100  6th Avenue S.W., Calgary, Alberta, at 8:00 a.m., Mountain Time. This special meeting will be held
for the following purposes:

1.

to approve the issuance of Encana common shares, no par value, to stockholders of Newfield Exploration Company,
a Delaware corporation (Newfield), in connection with the Agreement and Plan of Merger, dated as of October 31, 2018 (as it may be amended from time to time, the merger agreement), a copy of which is attached as Annex A
to the joint proxy statement/prospectus of which this notice is a part, by and among Encana, Neapolitan Merger Corp., a Delaware corporation and an indirect wholly-owned subsidiary of Encana (Merger Sub), and Newfield (the share
issuance proposal); and

2.

to approve the adjournment of the Encana special meeting, if necessary or appropriate, to solicit additional
proxies if there are not sufficient votes to approve the share issuance proposal (the Encana adjournment proposal).

This joint proxy statement/prospectus describes the proposals listed above in more detail. Please refer to the attached document,
including the merger agreement and all other annexes and any documents incorporated by reference, for further information with respect to the business to be transacted at the Encana special meeting. You are encouraged to read the entire
document carefully before voting. In particular, see the section entitled The Merger beginning on page 61 for a description of the transactions contemplated by the merger agreement, including the share
issuance contemplated by the share issuance proposal, and the section entitled Risk Factors beginning on page 39 for an explanation of the risks associated with the merger and the other transactions contemplated by the merger
agreement, including the share issuance.

The Encana board of directors (the Encana board) has (i) unanimously
determined that the terms of the merger agreement and the transactions contemplated thereby, including the merger and the share issuance, are in the best interests of Encana, (ii) unanimously approved the execution and delivery by Encana of the
merger agreement, the performance by Encana of its covenants and agreements contained therein and the consummation of the transactions contemplated by the merger agreement, including the merger and the share issuance, upon the terms and subject to
the conditions therein, (iii) unanimously directed that the merger agreement be submitted to Encana shareholders at the Encana special meeting to approve the share issuance, and (iv) unanimously resolved to recommend that Encana
shareholders approve the share issuance. The Encana board recommends that Encana shareholders vote FOR the share issuance proposal and FOR the Encana adjournment proposal.

The Encana board has fixed January 8, 2019 as the record date for determination of Encana shareholders entitled to receive notice of, and to
vote at, the Encana special meeting or any adjournments or postponements thereof. Only Encana shareholders of record at the close of business on the record date are entitled to receive notice of, and to vote at, the Encana special meeting.

YOUR VOTE IS VERY IMPORTANT REGARDLESS OF THE NUMBER OF SHARES THAT YOU OWN. The
merger between Encana and Newfield cannot be completed without the approval of the share issuance proposal by the affirmative vote of a majority of votes cast by Encana shareholders entitled to vote thereon and present in person or represented by
proxy at the Encana special meeting.

Whether or not you expect to attend the Encana special meeting in person, we urge you to submit a
proxy to have your shares voted as promptly as possible by either: (1) logging onto the website shown on your proxy card and following the instructions to vote online; (2) dialing the toll-free number shown on
your proxy card and following the instructions to vote by phone; or (3) signing and returning the enclosed proxy card in the postage-paid envelope provided, so that your shares may be represented and voted at the Encana special
meeting. Even if you plan to attend the Encana special meeting in person, we request that you complete, sign, date and return the enclosed proxy card and thus ensure that your Encana common shares will be represented at the Encana special
meeting if you are unable to attend.

If your shares are held in the name of a broker, bank, trustee or other nominee, please follow
the instructions on the voting instruction form furnished by such broker, bank, trustee or other nominee, as appropriate. If you have any questions concerning the share issuance proposal or the other transactions contemplated by the merger agreement
or this joint proxy statement/prospectus, would like additional copies or need help voting your Encana common shares, please contact Encanas proxy solicitors:

1407 Broadway, 27th Floor

New York, New York 10018

Call
Collect: 1-212-929-5500

Call Toll-Free:
1-800-322-2885

E-mail: Encana@mackenziepartners.com

130 King Street West, Suite 2950, P.O. Box 361

Toronto, Ontario M5X 1E2

Call
Toll-Free (within North America): 1-866-229-8166

Call Collect (outside North America):
1-416-867-2272

E-mail: contactus@kingsdaleadvisors.com

By order of the Board of Directors of Encana
Corporation

Nancy L. Brennan

Corporate Secretary

NEWFIELD EXPLORATION COMPANY

4 Waterway Square Place Suite 100

The Woodlands, Texas 77380

NOTICE OF SPECIAL MEETING OF STOCKHOLDERS TO BE HELD ON FEBRUARY 12, 2019

This is a notice that a special meeting (the Newfield special meeting) of stockholders (Newfield stockholders) of
Newfield Exploration Company, a Delaware corporation (Newfield), will be held on February 12, 2019 at the Four Seasons Hotel, Fairfield Ballroom, 1300 Lamar St., Houston, Texas 77010 at 9:00 a.m., Central Time. This special meeting will
be held for the following purposes:

1.

to adopt the Agreement and Plan of Merger, dated as of October 31, 2018 (as it may be amended from time to
time, the merger agreement), a copy of which is attached as Annex A to the joint proxy statement/prospectus of which this notice is a part, by and among Newfield, Encana Corporation, a Canadian corporation (Encana), and
Neapolitan Merger Corp., a Delaware corporation and an indirect wholly-owned subsidiary of Encana (Merger Sub), pursuant to which Merger Sub will merge with and into Newfield (the merger), with Newfield surviving the merger
as an indirect, wholly-owned subsidiary of Encana, and each outstanding share of Newfield common stock (with certain exceptions described in the accompanying joint proxy statement/prospectus) will be cancelled and converted into the right to receive
2.6719 Encana common shares pursuant to the merger agreement (the merger agreement proposal);

2.

to approve, on an advisory (non-binding) basis, the compensation that
may be paid or become payable to Newfields named executive officers in connection with the merger (the non-binding compensation advisory proposal); and

3.

to approve the adjournment of the Newfield special meeting, if necessary or appropriate, to solicit additional
proxies if there are not sufficient votes to adopt the merger agreement (the Newfield adjournment proposal).

This joint proxy statement/prospectus describes the proposals listed above in more detail, as well as other matters contemplated in
connection with the proposed merger. Please refer to the attached document, including the merger agreement and all other annexes and including any documents incorporated by reference, for further information with respect to the business to be
transacted at the Newfield special meeting. You are encouraged to read the entire document carefully before voting. In particular, see the section entitled The Merger beginning on page 61 for a description
of the transactions contemplated by the merger agreement, and the section entitled Risk Factors beginning on page 39 for an explanation of the risks associated with the merger and the other transactions
contemplated by the merger agreement.

Newfields board of directors (the Newfield board) has (i) unanimously
determined that the terms of the merger agreement and the transactions contemplated thereby, including the merger, are advisable, fair to, and in the best interests of, Newfield and Newfield stockholders, (ii) unanimously approved and declared
advisable the merger agreement and the transactions contemplated by the merger agreement, including the merger, (iii) unanimously approved the execution and delivery by Newfield of the merger agreement, the performance by Newfield of its
covenants and agreements contained therein and the consummation of the transactions contemplated by the merger agreement, including the merger, upon the terms and subject to the conditions contained therein, (iv) unanimously directed that the
merger agreement be submitted to Newfield stockholders at the Newfield special meeting to approve its adoption, (v) taken all actions necessary so that the restrictions on business combinations and stockholder vote requirements contained in
Section 203 of the Delaware General Corporation Law and any other applicable

law with respect to a moratorium, control share acquisition, business combination, fair price or other forms of anti-takeover laws that may purport
to be applicable will not apply with respect to or as a result of the entry into the merger agreement and the consummation of the transactions contemplated thereby, including the merger, and (vi) unanimously resolved to recommend that Newfield
stockholders approve the adoption of the merger agreement.

The Newfield board has fixed January 8, 2019 as the record date for determination of Newfield stockholders
entitled to receive notice of, and to vote at, the Newfield special meeting or any adjournments or postponements thereof. Only Newfield stockholders of record at the close of business on the record date are entitled to receive notice of, and to vote
at, the Newfield special meeting.

A complete list of registered Newfield stockholders entitled to vote at the Newfield special meeting
will be available for inspection at the principal place of business of Newfield at 4 Waterway Square Place, Suite 100, The Woodlands, Texas 77380, during regular business hours for a period of no less than ten (10) days before the Newfield
special meeting and at the place of the Newfield special meeting during the meeting.

YOUR VOTE IS VERY IMPORTANT REGARDLESS OF THE
NUMBER OF SHARES THAT YOU OWN. The merger between Newfield and Encana cannot be completed without the adoption of the merger agreement by the affirmative vote, in person or by proxy, of the holders of at least
662⁄3% of the issued and outstanding shares of Newfield common stock entitled to vote on the merger agreement proposal as of the record date for the Newfield
special meeting.

Whether or not you expect to attend the Newfield special meeting in person, we urge you to submit a proxy to have
your shares voted as promptly as possible by either: (1) logging onto the website shown on your proxy card and following the instructions to vote online; (2) dialing the toll-free number shown on your proxy card
and following the instructions to vote by phone; or (3) signing and returning the enclosed proxy card in the postage-paid envelope provided, so that your shares may be represented and voted at the Newfield special meeting.

Even if you plan to attend the Newfield special meeting in person, we request that you complete, sign, date and return the enclosed
proxy card and thus ensure that your Newfield common stock will be represented at the Newfield special meeting if you are unable to attend.

If your stock is held in a Newfield plan or in the name of a broker, bank, trustee or other nominee, please follow the instructions on the
voting instruction form furnished by the plan administrator or such broker, bank, trustee or other nominee, as appropriate. If you have any questions concerning the merger agreement proposal or the other transactions contemplated by the merger
agreement or this joint proxy statement/prospectus, would like additional copies or need help voting your shares of Newfield common stock, please contact Newfields proxy solicitor:

Innisfree M&A Incorporated

501 Madison Avenue, 20th Floor

New
York, New York 10022

Call Toll-Free:
1-888-750-5834

Banks and Brokers Call Collect:
1-212-750-5833

By order of the Board of Directors of Newfield Exploration Company

Lee K. Boothby

Chairman, President and Chief Executive Officer

ADDITIONAL INFORMATION

Both Encana and Newfield file annual, quarterly and current reports, proxy statements and other business and financial information with the
U.S. Securities and Exchange Commission (the SEC). Financial information about Encana and Newfield is provided in each companys annual financial statements and accompanying managements discussion and analysis for the year
ended December 31, 2017 and the nine months ended September 30, 2018.You may read and copy any materials that either Encana or Newfield files with the SEC at the SECs Public Reference Room at 100 F Street, N.E., Room 1580,
Washington, D.C. 20549. Please call the SEC at (800) 732-0330 for further information on the Public Reference Room. In addition, Encana and Newfield file reports and other business and financial
information with the SEC electronically, and the SEC maintains a website located at http://www.sec.gov containing this information. Such information regarding Encana is also available under Encanas profile on the System for Electronic Document
Analysis and Retrieval at www.sedar.com . You can also obtain these documents, free of charge, from Encana at https://www.encana.com/investors/financial/ or from Newfield at http://ir.newfield.com. The information contained on, or that may be
accessed through, Encanas and Newfields websites is not incorporated by reference into, and is not a part of, this joint proxy statement/prospectus.

Encana has filed a registration statement on Form S-4 with respect to the Encana common shares to
be issued in the merger, of which this joint proxy statement/prospectus forms a part. This joint proxy statement/prospectus constitutes the prospectus of Encana filed as part of the registration statement. As permitted by SEC rules, this joint
proxy statement/prospectus does not contain all of the information included in the registration statement or in the exhibits or schedules to the registration statement. You may read and copy the registration statement, including any amendments,
schedules and exhibits in the SECs reading room at the address set forth above or at the SECs website mentioned above. Statements contained in this joint proxy statement/prospectus as to the contents of any contract or other documents
referred to in this joint proxy statement/prospectus are not necessarily complete. In each case, you should refer to the copy of the applicable agreement or other document filed as an exhibit to the registration statement. This joint proxy
statement/prospectus incorporates important business and financial information about Encana and Newfield from documents that are not attached to this joint proxy statement/prospectus. This information is available to you without charge upon
your request. You can obtain the documents incorporated by reference into this joint proxy statement/prospectus, including copies of financial statements and managements discussion and analysis, free of charge by requesting them in
writing or by telephone from the appropriate company or its proxy solicitors at the following addresses and telephone numbers:

For Encana shareholders:

For Newfield stockholders:

Encana Corporation

Suite 4400, 500 Centre Street S.E., P.O. Box 2850

Calgary, Alberta, Canada, T2P 2S5

Attention: Corporate Secretary

(403) 645-2000

Newfield Exploration Company

4 Waterway Square Place, Suite 100

The Woodlands, Texas 77380

Attention: Investor Relations

(281) 210-5182

MacKenzie Partners, Inc.

1407 Broadway, 27th Floor

New York, New York 10018

Call Collect:
1-212-929-5500

Call Toll-Free:
1-800-322-2885

E-mail: Encana@mackenziepartners.com

Innisfree M&A Incorporated

501 Madison Ave, 20th Floor

New York, New York 10022

Call Toll-Free: 1-888-750-5834

Banks and Brokers may call collect:
1-212-750-5833

Kingsdale Advisors

130 King Street West, Suite 2950, P.O. Box 361

Toronto, Ontario M5X 1E2

Call Toll-Free (within North America):

1-866-229-8166

Call Collect (outside North America):
1-416-867-2272

E-mail: contactus@kingsdaleadvisors.com

If you would like to request any documents, please do so by February 6, 2019 in order to
receive them before the Encana special meeting or the Newfield special meeting, as applicable.

For a more detailed description of the
information incorporated by reference into this joint proxy statement/prospectus and how you may obtain it, see Where You Can Find More Information beginning on page 196.

ABOUT THIS JOINT PROXY STATEMENT/PROSPECTUS

This joint proxy statement/prospectus, which forms part of a registration statement on Form S-4
filed with the SEC by Encana, constitutes a prospectus of Encana under the Securities Act of 1933, as amended, with respect to the Encana common shares, to be issued to Newfield stockholders in connection with the merger. This joint proxy
statement/prospectus also constitutes a joint proxy statement for both Newfield and Encana under the Securities Exchange Act of 1934, as amended. This joint proxy statement/prospectus also constitutes a notice of meeting with respect to the special
meeting of Encana shareholders and a notice of meeting with respect to the special meeting of Newfield stockholders.

You should rely only
on the information contained in or incorporated by reference into this joint proxy statement/prospectus. No one has been authorized to provide you with information that is different from that contained in, or incorporated by reference into, this
joint proxy statement/prospectus. This joint proxy statement/prospectus is dated January 8, 2019, and you should assume that the information contained in this joint proxy statement/prospectus is accurate only as of such date. You should also assume
that the information incorporated by reference into this joint proxy statement/prospectus is only accurate as of the date of such information.

This joint proxy statement/prospectus does not constitute an offer to sell, or a solicitation of an offer to buy, any securities, or the
solicitation of a proxy in any jurisdiction to or from any person to whom it is unlawful to make any such offer or solicitation in such jurisdiction. Information contained in this joint proxy statement/prospectus regarding Encana has been provided
by Encana and information contained in this joint proxy statement/prospectus regarding Newfield has been provided by Newfield.

The following are some questions that you, as a shareholder (Encana shareholder) of Encana Corporation (Encana) or
a stockholder (Newfield stockholder) of Newfield Exploration Company (Newfield), may have regarding the merger, the issuance of common shares of Encana, without par value (Encana common shares), to Newfield
stockholders in connection with the merger and other matters being considered at the special meetings of Encana shareholders and Newfield stockholders (the Encana special meeting and the Newfield special meeting,
respectively) and the answers to those questions. Encana and Newfield urge you to carefully read the remainder of this joint proxy statement/prospectus because the information in this section does not provide all the information that might be
important to you with respect to the merger, the issuance of Encana common shares in connection with the merger and the other matters being considered at the Encana special meeting and the Newfield special meeting. Additional important information
is also contained in the annexes to and the documents incorporated by reference into this joint proxy statement/prospectus.

Q:

Why am I receiving this joint proxy statement/prospectus?

A:

You are receiving this joint proxy statement/prospectus because Encana, Newfield and Neapolitan Merger Corp., a
Delaware corporation and an indirect, wholly-owned subsidiary of Encana (Merger Sub), have entered into an Agreement and Plan of Merger, dated as of October 31, 2018 (as it may be amended from time to time, the merger
agreement), providing for the merger of Merger Sub with and into Newfield, with Newfield surviving the merger as an indirect wholly-owned subsidiary of Encana (the merger).

In order to complete the merger, Encana shareholders must approve the proposal to issue Encana common shares (such issuance, the share
issuance) to Newfield stockholders pursuant to the merger agreement (the share issuance proposal), and Newfield stockholders must approve the proposal to adopt the merger agreement (the merger agreement proposal), and
all other conditions to the merger must be satisfied or waived.

Encana and Newfield will hold separate special meetings to obtain these
approvals and vote on other related matters, including, in the case of Newfield, a vote to approve, on an advisory (non-binding) basis, the compensation that may be paid or become payable to Newfields
named executive officers in connection with the merger (the non-binding compensation advisory proposal).

This joint proxy statement/prospectus, which you should read carefully, contains important information about the merger, the share issuance and
other matters being considered at the Encana special meeting and the Newfield special meeting.

Q:

When and where is the Encana special meeting?

A:

The Encana special meeting will be held on February 12, 2019 at the Oddfellows Building, Ballroom
(Floor 4), 100  6th Avenue S.W., Calgary, Alberta at 8:00 a.m., Mountain Time.

Q:

When and where is the Newfield special meeting?

A:

The Newfield special meeting will be held on February 12, 2019 at the Four Seasons Hotel, Fairfield Ballroom,
1300 Lamar St., Houston, Texas 77010 at 9:00 a.m., Central Time.

Q:

What will Newfield stockholders receive for their shares of Newfield common stock in the merger?

A:

At the effective time of the merger (the effective time, and the date of the effective time the
closing date), each share of Newfield common stock, par value $0.01 per share (the Newfield common stock), issued and outstanding immediately prior to the effective time (other than shares of Newfield common stock
(a) owned or held in treasury by Newfield or any of its wholly-owned subsidiaries or (b) owned by Encana or any of its wholly-owned subsidiaries (including Merger Sub), which will automatically be canceled and

1

cease to exist and no consideration shall be delivered in exchange therefor (the shares of Newfield common stock described in clauses (a) and (b) together, excluded
shares)), will be cancelled and converted automatically into the right to receive 2.6719 Encana common shares (the exchange ratio) in certificated or book-entry form with cash paid in lieu of the issuance of fractional Encana
common shares, if any (the merger consideration).

In addition, Newfield will take all actions as may be
necessary so that at the effective time, each outstanding restricted stock award, time-based restricted stock unit award, performance-based restricted stock unit award and share of notional stock in respect of Newfield common stock will be treated
as described in The MergerTreatment of Newfield Equity Awards in the Merger beginning on page 134.

For additional
information regarding the consideration to be received in the merger, see the section entitled The MergerEffects of the Merger.

Q:

If I am a Newfield stockholder, how will I receive the merger consideration to which I am entitled?

A:

As soon as reasonably practicable after the effective time, an exchange agent will mail to each holder of
record of Newfield common stock (whose shares were cancelled and converted into the right to receive the merger consideration pursuant to the merger agreement) a letter of transmittal and instructions for use in effecting the surrender of
certificates of Newfield common stock (Newfield stock certificates) and book-entry shares representing shares of Newfield common stock (Newfield book-entry shares) in exchange for the merger consideration. Upon receipt by the
exchange agent of (i) either Newfield stock certificates or Newfield book-entry shares and (ii) a signed letter of transmittal and such other documents as may be required pursuant to such instructions, the holder of such shares will be
entitled to receive the merger consideration in exchange therefor.

Q:

What will holders of Newfield equity awards receive in the merger?

A:

Pursuant to the merger agreement, the following will occur at the effective time:

Restricted Stock Awards: All outstanding Newfield restricted stock awards will be cancelled and each holder of Newfield restricted stock
will be entitled to receive, on a fully vested basis, for each share of restricted stock subject to any such award, the merger consideration.

Time-Based Restricted Stock Units with a Cash Settlement Feature: All outstanding Newfield time-based restricted stock units with a cash
settlement feature will be cancelled and each holder of such restricted stock units will be entitled to receive, on a fully vested basis, for each such restricted stock unit, a cash payment of equivalent value to the merger consideration, based on
the volume weighted averages of the trading price of Encana common shares on each of the five consecutive trading days ending on the trading day that is three trading days prior to the effective time of the merger.

Time-Based Restricted Stock Units with a Stock Settlement Feature: All outstanding Newfield time-based restricted stock units with a
stock settlement feature will be cancelled and each holder of such restricted stock units will be entitled to receive, on a fully vested basis for each such restricted stock unit, the merger consideration.

Performance-Based Restricted Stock Units: All outstanding Newfield performance-based restricted stock units will be cancelled and will
convert into the right to receive the merger consideration, with the performance-based vesting conditions applicable to such Newfield performance-based restricted stock units deemed achieved based on the
determination of the compensation and management development committee (Newfield compensation committee) of the Newfield board of directors (the Newfield board), not to exceed 200% per Newfield performance-based restricted
stock unit.

Notional Stock: Any shares of Newfield notional stock held in connection with Newfields Nonqualified Deferred
Compensation Plan will convert into the right to receive a cash payment of equivalent value to the

2

merger consideration, based on the volume weighted averages of the trading price of Encana common shares on each of the five consecutive trading days ending on the trading day that is three
trading days prior to the effective time of the merger.

For additional information regarding the treatment of Newfield equity awards, see
the section entitled The MergerTreatment of Newfield Equity Awards in the Merger beginning on page 134.

Q:

Who will own Encana immediately following the merger?

A:

Encana and Newfield estimate that, upon completion of the merger, Encana shareholders as of immediately prior
to the merger will hold approximately 63.5% and Newfield stockholders as of immediately prior to the merger will hold approximately 36.5% of the outstanding common shares of Encana (without giving effect to any Encana common shares held by Newfield
stockholders prior to the merger). The exact equity stake of Newfield stockholders in Encana immediately following the effective time of the merger will depend on the number of Encana common shares and shares of Newfield common stock issued and
outstanding immediately prior to the effective time of the merger.

Q:

How important is my vote?

A:

Your vote FOR each proposal presented at the Encana special meeting and/or the
Newfield special meeting is very important, and you are encouraged to submit a proxy as soon as possible. The merger between Encana and Newfield cannot be completed without the approval of the share issuance proposal by the Encana shareholders and
the approval of the merger agreement proposal by Newfield stockholders.

Encana. Approval of the share issuance
proposal requires the affirmative vote of a majority of votes cast by Encana shareholders entitled to vote thereon and present in person or represented by proxy at the Encana special meeting. Abstentions are considered Encana common shares present
and entitled to vote and will have the same effect as a vote against the share issuance proposal. The failure of any Encana shareholder to submit a vote will not be counted in determining the votes cast in connection with this proposal
and therefore will have no effect on the outcome of the share issuance proposal. Approval of the proposal to adjourn the Encana special meeting, if necessary or appropriate, to solicit additional proxies in favor of the share issuance proposal if
there are not sufficient votes at the time of such adjournment to approve the share issuance (the Encana adjournment proposal) requires the affirmative vote of a majority of votes cast by Encana shareholders entitled to vote thereon and
present in person or represented by proxy at the Encana special meeting. Failure to vote and abstentions will not be counted as votes cast for or against the Encana adjournment proposal.

Newfield. Approval of the merger agreement proposal requires the affirmative vote, in person or by proxy, of the holders of at least 662⁄3% of the issued and outstanding shares of Newfield common stock entitled to vote thereon. The failure of any Newfield stockholder to submit a vote, or any abstention,
will have the same effect as voting against the merger agreement proposal. Approval of the non-binding compensation advisory proposal requires the affirmative vote of a majority of votes cast by holders of the
issued and outstanding shares of Newfield common stock entitled to vote thereon and present in person or represented by proxy at the Newfield special meeting. Abstentions are considered shares of Newfield common stock present and entitled to vote
and will have the same effect as votes against the non-binding compensation advisory proposal. Since the non-binding compensation advisory proposal is not
binding, if the merger agreement is adopted by Newfield stockholders and the merger is completed, the compensation that is the subject of the non-binding compensation advisory proposal, which includes amounts
Encana or Newfield are contractually obligated to pay, would still be paid regardless of the outcome of the advisory (non-binding) vote. Approval of the proposal to adjourn the Newfield special meeting, if
necessary or appropriate, to solicit additional proxies in favor of the merger agreement proposal if there are not sufficient votes at the time of such adjournment to adopt the merger agreement (the Newfield adjournment proposal)
requires the affirmative vote of a majority of votes cast by holders of the issued and outstanding

3

shares of Newfield common stock entitled to vote thereon and present in person or represented by proxy at the Newfield special meeting. Abstentions are considered shares of Newfield common stock
present and entitled to vote and will have the same effect as votes against the Newfield adjournment proposal.

Q:

How do the Encana board and the Newfield board recommend that I vote?

A:

The Encana board of directors (the Encana board) has (i) unanimously determined that the terms
of the merger agreement and the transactions contemplated thereby, including the merger and the share issuance, are in the best interests of Encana, (ii) unanimously approved the execution and delivery by Encana of the merger agreement, the
performance by Encana of its covenants and agreements contained therein and the consummation of the transactions contemplated by the merger agreement, including the merger and the share issuance, upon the terms and subject to the conditions therein,
(iii) unanimously directed that the merger agreement be submitted to Encana shareholders at the Encana special meeting to approve the share issuance, and (iv) unanimously resolved to recommend that Encana shareholders approve the share
issuance. For a detailed description of the various factors considered by the Encana board, see the section entitled The MergerRecommendation of the Encana Board and Reasons for the Merger.

The Newfield board, after considering the various factors described
under The MergerRecommendation of the Newfield Board and Reasons for the Merger, the comprehensive process conducted by the Newfield board and the alternatives to the merger (including remaining as a stand-alone company), has
(i) unanimously determined that the terms of the merger agreement and the transactions contemplated thereby, including the merger, are advisable, fair to, and in the best interests of, Newfield and Newfield stockholders, (ii) unanimously
approved and declared advisable the merger agreement and the transactions contemplated by the merger agreement, including the merger, (iii) unanimously approved the execution and delivery by Newfield of the merger agreement, the performance by
Newfield of its covenants and agreements contained therein and the consummation of the transactions contemplated by the merger agreement, including the merger, upon the terms and subject to the conditions contained therein, (iv) unanimously
directed that the merger agreement be submitted to Newfield stockholders at the Newfield special meeting to approve its adoption, (v) taken all actions necessary so that the restrictions on business combinations and stockholder vote
requirements contained in Section 203 of the Delaware General Corporation Law (the DGCL) and any other applicable law with respect to a moratorium, control share acquisition, business combination,
fair price or other forms of anti-takeover laws that may purport to be applicable will not apply with respect to or as a result of the entry into the merger agreement and the consummation of the transactions contemplated thereby,
including the merger, and (vi) unanimously resolved to recommend that Newfield stockholders approve the adoption of the merger agreement.

Will the Encana common shares received at the time of completion of the merger be traded on an exchange?

A:

Yes. It is a condition to the consummation of the merger that the Encana common shares to be issued to Newfield
stockholders in connection with the merger be authorized for listing on the NYSE, subject to official notice of issuance, and the TSX, subject to satisfaction of customary listing conditions of the TSX. Shares of Newfield common stock currently
trade on the NYSE under the stock symbol NFX. When the merger is completed, the Newfield common stock currently listed on the NYSE will cease to be traded on the NYSE and will be deregistered under the Securities Exchange Act of 1934, as
amended (the Exchange Act).

4

Q:

How will Encana shareholders be affected by the merger?

A:

Upon completion of the merger, each Encana shareholder will hold the same number of Encana common shares that
such shareholder held immediately prior to completion of the merger. As a result of the merger, Encana shareholders will own shares in a larger company with more assets. However, because in connection with the merger, Encana will be issuing
additional Encana common shares to Newfield stockholders in exchange for their shares of Newfield common stock, each outstanding Encana common share immediately prior to the merger will represent a smaller percentage of the aggregate number of
Encana common shares issued and outstanding after the merger.

Q:

Is the transaction expected to be taxable to Newfield stockholders for U.S. federal income tax purposes?

A:

Yes. For U.S. holders (as such term is defined below under The MergerMaterial U.S. Federal Income
Tax Consequences of the Merger), the receipt of the merger consideration in exchange for Newfield common stock pursuant to the merger will be a taxable transaction for U.S. federal income tax purposes. In general, a U.S. holder of Newfield
common stock that receives Encana common shares in connection with the merger will recognize gain or loss equal to the difference, if any, between (1) the fair market value of the Encana common shares received and (2) such U.S.
holders adjusted tax basis in its shares of Newfield common stock exchanged. The deductibility of loss, if any, of a U.S. holder of Newfield common stock as a result of the merger may be subject to limitation for U.S. federal income tax
purposes. A U.S. holder will be subject to U.S. federal income tax on any gain recognized without a corresponding receipt of cash. Newfield stockholders should consult their tax advisors regarding the particular tax consequences of the exchange of
Newfield common stock for the merger consideration pursuant to the merger in light of their particular circumstances (including the application and effect of any state, local or foreign income and other tax laws). For a more detailed discussion of
the U.S. federal income tax consequences of the merger to Newfield stockholders, see The MergerMaterial U.S. Federal Income Tax Consequences of the Merger.

Q:

Are there any unique Canadian tax considerations that Newfield stockholders should be aware of in obtaining
shares of a Canadian company?

A:

Yes. An Encana shareholder who is a non-resident of Canada, and who
will not use or hold Encana common shares in a business carried on in Canada, will not be subject to Canadian tax on the disposition of such shares unless such shares are taxable Canadian property to such holder. Any dividends paid in
respect of the Encana common shares to persons who are non-residents of Canada will be subject to Canadian withholding tax at the rate of 25% unless the rate is reduced under the provisions of an applicable
tax treaty. See the section entitled The MergerMaterial Canadian Federal Income Tax Consequences.

Q:

When do Encana and Newfield expect to complete the merger?

A:

Encana and Newfield currently expect to complete the merger in the first quarter of 2019. However, neither
Encana nor Newfield can predict the actual date on which the merger will be completed, nor can the parties ensure that the merger will be completed, because completion is subject to conditions beyond either companys control. See the sections
entitled The MergerRegulatory Approvals Required to Complete the Merger and The Merger AgreementConditions to Completion of the Merger.

Q:

What happens if the merger is not completed?

A:

If the merger agreement is not adopted by Newfield stockholders, the share issuance is not approved by Encana
shareholders or the merger is not completed for any other reason, Newfield stockholders will not receive any payment for shares of Newfield common stock they own. Instead, Newfield will remain an independent public company, Newfield common stock
will continue to be listed and traded on the NYSE and registered under the Exchange Act and Newfield will continue to file periodic reports with the SEC.

5

Under specified circumstances, Newfield and/or Encana may be required to reimburse the other
partys expenses or pay a termination fee upon termination of the merger agreement, as described under The Merger AgreementExpenses and Termination Fees Relating to the Termination of the Merger Agreement.

Q:

How many votes may I cast?

A:

Each outstanding Encana common share entitles its holder of record to one vote on each matter to be considered
at the Encana special meeting. Only Encana shareholders who held Encana common shares at the close of business on January 8, 2019 are entitled to vote at the Encana special meeting and any adjournment or postponement of the Encana special meeting,
so long as such shares remain outstanding on the date of the Encana special meeting.

Each outstanding share of Newfield
common stock entitles its holder of record to one vote on each matter to be considered at the Newfield special meeting. Only Newfield stockholders who held shares of Newfield common stock at the close of business on January 8, 2019 are entitled to
vote at the Newfield special meeting and any adjournment or postponement of the Newfield special meeting, so long as such shares remain outstanding on the date of the Newfield special meeting.

Q:

Who can vote at, and what are the record dates of, each of the Encana special meeting and the Newfield
special meeting?

A:

All Encana shareholders who hold Encana common shares of record at the close of business on January 8, 2019,
the record date for the Encana special meeting, are entitled to receive notice of and to vote at the Encana special meeting.

All Newfield stockholders who hold shares of Newfield common stock of record at the close of business on January 8, 2019, the record date for
the Newfield special meeting, are entitled to receive notice of and to vote at the Newfield special meeting.

Q:

What constitutes a quorum at each of the Encana special meeting and the Newfield special meeting?

A:

In order for business to be conducted at the Encana and Newfield special meetings, a quorum must be present.

A quorum at the Encana special meeting requires the presence of at least two persons present in person, each being an
Encana shareholder or duly appointed proxyholder of an Encana shareholder, together holding at least 25% of the total issued and outstanding Encana common shares entitled to vote at the Encana special meeting.

A quorum at the Newfield special meeting requires the presence, in person or by proxy, of holders of a majority of the issued and outstanding
shares of Newfield common stock entitled to vote at the Newfield special meeting.

Q:

What do I need to do now?

A:

After you have carefully read and considered the information contained or incorporated by reference into this
joint proxy statement/prospectus, please submit your proxy via the Internet or by telephone in accordance with the instructions set forth on the enclosed proxy card, or complete, sign, date and return the enclosed proxy card in the postage-prepaid
envelope provided as soon as possible so that your shares will be represented and voted at the Encana special meeting and/or the Newfield special meeting, as applicable.

Additional information on voting procedures can be found under the section entitled Encana Special Meeting and under the section
entitled Newfield Special Meeting.

6

Q:

How will my proxy be voted?

A:

If you submit your proxy via the Internet, by telephone or by completing, signing, dating and returning the
enclosed proxy card, your proxy will be voted in accordance with your instructions.

Additional information on voting
procedures can be found under the section entitled Encana Special Meeting and under the section entitled Newfield Special Meeting.

Q:

Who will count the votes?

A:

The votes at the Encana special meeting will be counted by Encanas registrar and transfer agent AST Trust
Company (Canada). The votes at the Newfield special meeting will be counted by Broadridge Financial Solutions, Inc. an independent third party.

Q:

May I vote in person?

A:

Yes. If you are a registered Encana shareholder of record at the close of business on January 8, 2019, or a
Newfield stockholder of record at the close of business on January 8, 2019, you may attend the Encana special meeting or Newfield special meeting, as applicable and vote your shares in person, in lieu of submitting your proxy by Internet, telephone
or by completing, signing, dating and returning the enclosed proxy card. Please note attendance at the Encana special meeting or the Newfield special meeting, as applicable, alone will not cause the voting of your shares; you must affirmatively vote
the proxy card or meeting ballot provided.

If you are a beneficial owner of Encana common shares or a beneficial owner
of Newfield common stock, you are also invited to attend the Encana special meeting or the Newfield special meeting, as applicable. However, because you are not the Encana shareholder of record or Newfield stockholder of record, as applicable, you
may not vote your shares in person at the Encana special meeting or the Newfield special meeting, as applicable, unless you request and obtain a proxy issued in your own name from your bank, broker or nominee.

If you appoint a non-management proxyholder, please make sure they are aware and ensure they will
attend the applicable special meeting with the proper authority from you, the Encana shareholder or Newfield stockholder, as applicable, for your vote to count.

Q:

What must I bring to attend my special meeting?

A:

Only Encana shareholders of record and/or Newfield stockholders of record, as of the close of business on the
applicable record date, beneficial owners of Encana common shares or beneficial owners of Newfield common stock as of the close of business on the applicable record date, holders of valid proxies for the Encana special meeting or Newfield special
meeting, as applicable and invited guests of Encana or Newfield, as applicable, may attend the Encana special meeting or Newfield special meeting, as applicable. All attendees should be prepared to present government-issued photo identification
(such as a drivers license or passport) for admittance. The additional items, if any, that attendees must bring depend on whether they are Encana shareholders or Newfield stockholders of record, as applicable, beneficial owners of Encana
common shares or beneficial owners of Newfield common stock or proxy holders.

Additional information on attending the
Encana special meeting and the Newfield special meeting can be found under the section entitled Encana Special Meeting and under the section entitled Newfield Special Meeting.

Q:

What should I do if I receive more than one set of voting materials for the Encana special meeting or the
Newfield special meeting?

A:

You may receive more than one set of voting materials for the Encana special meeting, the Newfield special
meeting or both, including multiple copies of this joint proxy statement/prospectus and multiple proxy cards

7

or voting instruction forms. For example, if you hold your Encana common shares or Newfield common stock in more than one brokerage account, you will receive a separate voting instruction form
for each brokerage account in which you hold shares. If you are a holder of record and your shares are registered in more than one name, you will receive more than one proxy card. Please submit each separate proxy or voting instruction form that you
receive by following the instructions set forth in each separate proxy or voting instruction form.

Q:

Whats the difference between holding shares as an Encana shareholder or a Newfield stockholder of
record and holding shares as a beneficial owner of Encana common shares or Newfield common stock?

A:

If your Encana common shares are registered directly in your name with Encanas registrar and transfer
agent, AST Trust Company (Canada), or your shares of Newfield common stock are registered directly in your name with Newfields transfer agent, American Stock Transfer & Trust Company, LLC, you are considered, with respect to those
shares, to be the Encana shareholder of record, in the case of Encana, or the Newfield stockholder of record, in the case of Newfield. If you are such a shareholder or stockholder of record, as applicable, then this joint proxy statement and your
proxy card have been sent directly to you by Encana or Newfield, as applicable.

If your Encana common shares or Newfield
common stock are held through a bank, broker or other nominee, you are considered the beneficial owner of the Encana common shares or Newfield common stock held in street name. In that case, this proxy statement has been forwarded to you
by your bank, broker or other nominee. As the beneficial owner, you have the right to direct your bank, broker or other nominee how to vote your shares by following their instructions for voting, and you are also invited to attend in person the
Encana special meeting or the Newfield special meeting, as applicable. However, because you are not the Encana shareholder or Newfield stockholder of record, you may not vote your Encana common shares in person at the Encana special meeting or your
shares of Newfield common stock at the Newfield special meeting, as applicable, unless you request and obtain a proxy issued in your own name from your bank, broker or nominee.

If you appoint a non-management proxyholder, please make sure they are aware and ensure they will
attend the applicable special meeting with the proper authority from you, the Encana shareholder or Newfield stockholder, for your vote to count.

Q:

If my Encana common shares or shares of Newfield common stock are held in street name by my
broker, bank or other nominee, will my broker, bank or other nominee automatically vote my shares for me?

A:

No. If your Encana common shares or shares of Newfield common stock, as applicable, are held in the name of a
broker, bank or other nominee, you will receive separate instructions from your broker, bank or other nominee describing how to vote your shares. The availability of Internet or telephonic voting will depend on the nominees voting process.
Please check with your broker, bank or other nominee and follow the voting procedures provided by your broker, bank or other nominee on your voting instruction form.

You should instruct your broker, bank or other nominee how to vote your Encana common shares or shares of Newfield common stock, as applicable.
Under the rules applicable to broker-dealers, your broker, bank or other nominee does not have discretionary authority to vote your shares on any of the proposals scheduled to be voted on at the Encana special meeting or the Newfield special
meeting. A so-called broker non-vote results when banks, brokers and other nominees return a valid proxy voting upon a matter or matters for which the
applicable rules provide discretionary authority but do not vote on a particular proposal because they do not have discretionary authority to vote on the matter and have not received specific voting instructions from the beneficial owner of such
shares. Encana and Newfield do not expect any broker non-votes at the Encana special meeting or Newfield special meeting because the rules applicable to banks, brokers and other nominees only provide brokers
with discretionary authority to vote on proposals that are considered routine, whereas each of the proposals to be presented at the Encana special meeting and

8

Newfield special meeting are considered non-routine. As a result, no broker will be permitted to vote your Encana common shares at the Encana special
meeting or your shares of Newfield common stock at the Newfield special meeting without receiving instructions. Failure to instruct your broker on how to vote your shares will have no effect on the outcome of the share issuance proposal or the non-binding compensation advisory proposal, but will have the same effect as a vote against the approval of the merger agreement proposal.

Additional information on voting procedures can be found under the section entitled Encana Special Meeting and under the section
entitled Newfield Special Meeting.

Q:

How do I vote Encana common shares held in an Encana employee benefit plan?

A.

If your Encana common shares are held in an Encana employee benefit plan, you will receive a separate voting
direction card. The trustee and/or plan administrator of the applicable Encana employee benefit plan will vote your Encana common shares in accordance with the instructions on your returned direction card.

If you do not timely return a direction card, the trustee and/or plan administrator will vote your Encana common shares in accordance with
their normal process. If you return a direction card with no instructions, the trustee and/or plan administrator will vote your Encana common shares FOR the share issuance proposal and FOR the Encana adjournment proposal.
Please note that the direction cards have an earlier return date than the proxy cards. Please review your direction card for the date by which your instructions must be received in order for your Encana common shares to be voted.

In the case of Internet or telephone voting, you should have your direction card in hand and retain the card until you have completed the
voting process. If you vote by Internet or telephone, you do not need to return the direction card by mail.

Please note that no votes will
be accepted at the Encana special meeting in respect of Encana common shares held in an Encana employee benefit plan and that all such votes must be voted prior to the Encana special meeting.

Q:

How do I vote shares of Newfield common stock held in Newfields 401(k) plan?

A.

If your shares of Newfield common stock are held in Newfields 401(k) plan, you will receive a separate
voting direction card. The trustee of the Newfield 401(k) plan will vote your shares of Newfield common stock in accordance with the instructions on your returned direction card.

If you do not timely return a direction card or if you return a direction card with no instructions, the trustee will vote your shares of
Newfield common stock in proportion to the voting directions received from all plan participants who properly vote. Please note that the direction cards have an earlier return date than the proxy cards. Please review your direction card for the date
by which your instructions must be received in order for your shares of Newfield common stock to be voted.

In the case of Internet or
telephone voting, you should have your direction card in hand and retain the card until you have completed the voting process. If you vote by Internet or telephone, you do not need to return the direction card by mail.

Please note that no votes will be accepted at the Newfield special meeting in respect of shares of Newfield common stock held in
Newfields 401(k) plan and that all such votes must be voted prior to the Newfield special meeting.

Q:

What do I do if I am an Encana shareholder and I want to revoke my proxy?

A:

Encana shareholders of record may revoke their proxies at any time before their Encana common shares are voted
at the Encana special meeting in any of the following ways:



sending a written notice of revocation to Encana at Suite 4400, 500 Centre Street S.E., Calgary, Alberta T2P 2S5,
Canada Attention: Corporate Secretary, which must be received before their shares are voted at the Encana special meeting;

9



properly submitting a later-dated, new proxy card, which must be received by 8:00 a.m., Mountain Time, on
February 8, 2019 (in which case only the later-dated proxy is counted and the earlier proxy is revoked);



submitting a proxy via the Internet or by telephone at a later date, which must be received by 8:00 a.m.,
Mountain Time, on February 8, 2019 (in which case only the later-dated proxy is counted and the earlier proxy is revoked); or



attending the Encana special meeting and voting in person; attendance at the Encana special meeting will not,
however, in and of itself, constitute a vote or revocation of a prior proxy.

Beneficial owners of Encana common shares
may change their voting instruction by submitting new voting instructions to the brokers, banks or other nominees that hold their shares of record or by requesting a proxy issued in their own name from such broker, bank or other nominee and voting
in person at the Encana special meeting. In addition, shareholders who hold Encana common shares in an Encana employee benefit plan may revoke or change their proxy via any of the foregoing methods, except that a new employee benefit plan
participant proxy must be received by 8:00 a.m., Mountain Time, on February 4, 2019.

Additional information can be found under the section
entitled Encana Special Meeting.

Q:

What do I do if I am a Newfield stockholder and I want to revoke my proxy?

A:

Newfield stockholders of record may revoke their proxies at any time before their shares of Newfield common
stock are voted at the Newfield special meeting in any of the following ways:



sending a written notice of revocation to Newfield at Newfield Exploration Company, 4 Waterway Square Place,
Suite 100, The Woodlands, Texas 77380, Attention: Investor Relations, which must be received before their shares are voted at the Newfield special meeting;



properly submitting a later-dated, new proxy card, which must be received before their shares are voted at the
Newfield special meeting (in which case only the later-dated proxy is counted and the earlier proxy is revoked);



submitting a proxy via the Internet or by telephone at a later date, which must be received
by 11:59 p.m., Eastern Time, on February 11, 2019 (in which case only the later-dated proxy is counted and the earlier proxy is revoked); or



attending the Newfield special meeting and voting in person; attendance at the Newfield special meeting will not,
however, in and of itself, constitute a vote or revocation of a prior proxy.

Beneficial owners of Newfield common stock
may change their voting instruction by submitting new voting instructions to the brokers, banks or other nominees that hold their shares of record or by requesting a legal proxy from such broker, bank or other nominee and voting in
person at the Newfield special meeting. In addition, stockholders who hold shares of Newfield common stock in Newfields 401(k) plan may revoke or change their proxy via any of the foregoing methods, except that a new 401(k) plan participant
proxy must be received by 11:59 p.m., Eastern Time, on February 8, 2019.

Additional information can be found under the section entitled
Newfield Special Meeting.

Q:

Are there any risks that I should consider as an Encana shareholder or Newfield stockholder in deciding how
to vote?

A:

Yes. You should read and carefully consider the risk factors set forth in the section entitled
Risk Factors beginning on page 39. You also should read and carefully consider the risk factors of Encana and Newfield contained in the documents that are incorporated by reference in this joint proxy statement/prospectus.

10

Q:

What happens if I sell or otherwise transfer my Encana common shares before the Encana special meeting?

A:

The record date for Encana shareholders entitled to vote at the Encana special meeting is January 8, 2019,
which is earlier than the date of the Encana special meeting. If you sell or otherwise transfer your shares after the record date but before the Encana special meeting, unless special arrangements (such as provision of a proxy) are made between you
and the person to whom you transfer your shares and each of you notifies Encana in writing of such special arrangements, you will retain your right to vote such shares at the Encana special meeting but will otherwise transfer ownership of and the
economic interest in your Encana common shares.

Q:

What happens if I sell or otherwise transfer my shares of Newfield common stock before the Newfield special
meeting?

A:

The record date for Newfield stockholders entitled to vote at the Newfield special meeting is January 8, 2019,
which is earlier than the date of the Newfield special meeting. If you sell or otherwise transfer your shares after the record date but before the Newfield special meeting, unless special arrangements (such as provision of a proxy) are made between
you and the person to whom you transfer your shares and each of you notifies Newfield in writing of such special arrangements, you will retain your right to vote such shares at the Newfield special meeting but will otherwise transfer ownership of
and the economic interest in your shares of Newfield common stock.

Q:

What happens if I sell or otherwise transfer my shares of Newfield common stock before the completion of the
merger?

A:

Only Newfield stockholders at the effective time will become entitled to receive the merger consideration. If
you sell your shares of Newfield common stock prior to the completion of the merger, you will not become entitled to receive the merger consideration by virtue of the merger.

Q:

Do any of the officers or directors of Newfield have interests in the merger that may differ from or be in
addition to my interests as a Newfield stockholder?

A:

In considering the recommendation of the Newfield board that Newfield stockholders vote to approve the merger
agreement proposal, the non-binding compensation advisory proposal and the Newfield adjournment proposal, Newfield stockholders should be aware that, aside from their interests as stockholders of Newfield,
some of Newfields directors and executive officers have interests in the merger that may be different from, or in addition to, the interests of Newfield stockholders generally. The Newfield board was aware of and considered these potential
interests, among other matters, in evaluating and negotiating the merger agreement and the transactions contemplated therein, in approving the merger and in recommending the approval of the merger agreement proposal, the non-binding compensation advisory proposal and the Newfield adjournment proposal.

For
more information and quantification of these interests, please see The MergerInterests of Certain Newfield Directors and Executive Officers in the Merger.

Q:

If I am an Encana shareholder and I oppose the share issuance proposal or I am a Newfield stockholder and I
oppose the merger agreement proposal, but both proposals are approved, what are my rights?

A:

Encana shareholders may vote against the share issuance proposal if they do not favor the merger. However, if
the share issuance proposal is approved, Encana shareholders who oppose the share issuance proposal are not entitled to dissenters or appraisal rights under Canadian law in connection with the issuance of Encana common shares as contemplated
by the merger agreement.

11

Newfield stockholders may vote against the merger agreement proposal if they do not favor
the merger. However, if the merger agreement proposal is approved, because shares of Newfield common stock are listed on the NYSE and Newfield stockholders are not required to receive consideration other than Encana common shares, which are also
listed on the NYSE, with cash paid in lieu of the issuance of fractional Encana common shares, if any, in the merger, Newfield stockholders are not entitled to exercise dissenters or appraisal rights under Delaware law in connection with the
merger.

Q:

Where can I find voting results of the Encana special meeting and the Newfield special meeting?

A:

Newfield and Encana intend to announce their respective preliminary voting results at each of the Newfield and
Encana special meetings and publish the final results in Current Reports on Form 8-K that will be filed with the SEC following the Newfield special meeting and the Encana special meeting, respectively. All
reports that Newfield and Encana file with the SEC are publicly available when filed. See the section entitled Where You Can Find More Information.

Q:

How can I find more information about Encana and Newfield?

A:

You can find more information about Encana and Newfield from various sources described in the section entitled
Where You Can Find More Information.

Q:

Who can answer any questions I may have about the Encana special meeting, the Newfield special meeting, the
merger, or the transactions contemplated by the merger agreement, including the share issuance?

A:

If you have any questions about the Encana special meeting, the Newfield special meeting, the merger, the share
issuance, how to submit your proxy or if you need additional copies of this joint proxy statement/prospectus or documents incorporated by reference herein, the enclosed proxy card or voting instructions, you should contact:

The following summary highlights selected information described in more detail elsewhere in this joint proxy statement/prospectus and the
documents incorporated by reference into this joint proxy statement/prospectus and may not contain all the information that may be important to you. To understand the merger and the matters being voted on by Newfield stockholders and Encana
shareholders at their respective special meetings more fully, and to obtain a more complete description of the legal terms of the merger agreement and the agreements related thereto, you should carefully read this entire document, including the
annexes, and the documents to which Encana and Newfield refer you. Each item in this summary includes a page reference directing you to a more complete description of that topic. See Where You Can Find More Information.

The Parties (see pages 46, 47)

Encana Corporation

Encana is a
leading North American energy producer that is focused on developing its multi-basin portfolio of oil, natural gas liquids (NGLs) and natural gas producing plays. Encanas operations also include the marketing of oil, NGLs and
natural gas. All of Encanas reserves and production are located in North America.

Encanas common shares are listed and posted
for trading on the NYSE and the TSX under the symbol ECA. Encana is incorporated under the Canada Business Corporations Act (the CBCA) and was formed in 2002 through the business combination of two predecessor companies.

The principal executive offices of Encana are located at Suite 4400, 500 Centre Street S.E., P.O. Box 2850, Calgary, Alberta, T2P 2S5 Canada
and its telephone number is (403) 645-2000.

Neapolitan Merger Corp.

Neapolitan Merger Corp., a Delaware corporation (referred to previously in this joint proxy statement/prospectus as Merger Sub), is a
wholly-owned indirect subsidiary of Encana. Merger Sub is newly formed, and was organized for the purpose of consummating the merger. Merger Sub has engaged in no business activities to date and it has no material assets or liabilities of any kind,
other than those incident to its formation and those incurred in connection with the merger. Merger Subs address is 370 17th Street, Suite 1700, Denver, Colorado 80202.

Newfield Exploration Company

Newfield is a Delaware corporation, incorporated in 1988 and publicly traded on the NYSE since 1993. Newfield has been a member of the S&P
500 Index since 2010. Newfields U.S. operations are onshore and focus primarily on large scale, liquids-rich resource plays in the Anadarko Basin of Oklahoma, the Williston Basin of North Dakota and the Uinta Basin of Utah. In addition,
Newfield has oil assets offshore of China and gas assets in the Arkoma Basin of Oklahoma.

Shares of Newfield common stock are listed for
trading on the NYSE under the symbol NFX. The principal executive offices of Newfield are located at 4 Waterway Square Place, Suite 100, The Woodlands, Texas 77380 and its telephone number is (281)
210-5100.

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Encana Special Meeting (see page 48)

Date, Time and Place.The Encana special meeting will be held on February 12, 2019 at the Oddfellows
Building, Ballroom (Floor 4), 100  6th Avenue S.W., Calgary, Alberta, at 8:00 a.m., Mountain Time.

Purpose.The Encana special meeting is being held to consider and vote on the following proposals:



Proposal 1.To approve the issuance of Encana common shares to Newfield
stockholders in connection with the merger (referred to previously in this joint proxy statement/prospectus as the share issuance proposal); and



Proposal 2.To approve the adjournment of the Encana special meeting, if
necessary or appropriate, to solicit additional proxies if there are not sufficient votes to approve the share issuance proposal (referred to previously in this joint proxy statement/prospectus as the Encana adjournment proposal).

Record Date; Voting Rights.The record date for the determination of Encana
shareholders entitled to notice of and to vote at the Encana special meeting is January 8, 2019. Only Encana shareholders who held Encana common shares of record at the close of business on January 8, 2019 are entitled to vote at the Encana special
meeting and any adjournment or postponement of the Encana special meeting so long as such shares remain outstanding on the date of the Encana special meeting. Each issued and outstanding Encana common share entitles its holder of record to one vote
on each matter to be considered at the Encana special meeting.

Quorum.In order for business to be
conducted at the Encana special meeting, a quorum must be present. A quorum at the Encana special meeting requires the presence of at least two persons present in person, each being an Encana shareholder or duly appointed proxyholder of an Encana
shareholder, together holding at least 25% of the total issued and outstanding Encana common shares entitled to vote at the Encana special meeting. For purposes of determining whether there is a quorum, all shares that are present, including
abstentions, will count towards the quorum.

Vote Required.The affirmative vote of a majority of votes
cast by Encana shareholders entitled to vote thereon and present in person or represented by proxy at the Encana special meeting is required to approve each of the share issuance proposal and the Encana adjournment proposal.

As of the record date, there were 952,507,693 Encana common shares outstanding. As of the record date, Encana directors and executive
officers, as a group, beneficially owned and were entitled to vote 1,252,871 Encana common shares, or approximately 0.1% of the issued and outstanding Encana common shares. As of the record date, Encanas directors and executive officers did
not own any shares of Newfield common stock.

Newfield Special Meeting (see page 54)

Date, Time and Place.The Newfield special meeting will be held on February 12, 2019 at the Four Seasons
Hotel, Fairfield Ballroom, 1300 Lamar St., Houston, Texas 77010 at 9:00 a.m., Central Time.

Purpose.The Newfield special meeting is being held to consider and vote on the following proposals:



Proposal 1.To adopt the merger agreement, a copy of which is attached as
Annex A to this joint proxy statement/prospectus, pursuant to which each outstanding share of Newfield common stock (other than excluded shares) will be cancelled and converted into the right to receive 2.6719 Encana common shares with cash
paid in lieu of the issuance of fractional Encana common shares, if any (referred to previously in this joint proxy statement/prospectus as the merger agreement proposal).



Proposal 2.To approve, on an advisory
(non-binding) basis, the compensation that may be paid or become payable to Newfields named executive officers in connection with the merger (referred to

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previously in this joint proxy statement/prospectus as the non-binding compensation advisory proposal), discussed under the heading The
MergerInterests of Certain Newfield Directors and Executive Officers in the Merger.



Proposal 3.To approve the adjournment of the Newfield special meeting, if
necessary or appropriate, to solicit additional proxies if there are not sufficient votes to adopt the merger agreement (referred to previously in this joint proxy statement/prospectus as the Newfield adjournment proposal).

Record Date; Voting Rights.The record date for the determination of Newfield stockholders entitled to
notice of and to vote at the Newfield special meeting is January 8, 2019. Only Newfield stockholders who held shares of Newfield common stock at the close of business on January 8, 2019 are entitled to vote at the Newfield special meeting and any
adjournment or postponement of the Newfield special meeting, so long as such shares remain outstanding on the date of the Newfield special meeting. Each outstanding share of Newfield common stock entitles its holder of record to one vote on each
matter to be considered at the Newfield special meeting.

Quorum.In order for business to be conducted
at the Newfield special meeting, a quorum must be present. A quorum at the Newfield special meeting requires the presence, in person or by proxy, of holders of a majority of the issued and outstanding shares of Newfield common stock entitled to vote
at the Newfield special meeting. For purposes of determining whether there is a quorum, all shares that are present, including abstentions, and entitled to vote will count towards the quorum.

Vote Required.The votes required for each proposal are as follows:



Proposal 1the merger agreement proposal.The affirmative vote, in person
or by proxy, of the holders of at least 662⁄3% of the issued and outstanding shares of Newfield common stock entitled to vote thereon.



Proposal 2the non-binding compensation advisory
proposal.The affirmative vote of a majority of votes cast by holders of the issued and outstanding shares of Newfield common stock entitled to vote thereon and present in person or represented by proxy at the Newfield
special meeting. Since the votes for the merger-related non-binding compensation advisory proposal are non-binding, if the merger agreement is adopted by Newfield
stockholders and the merger is completed, the compensation that is the subject of the non-binding compensation advisory proposal, which includes amounts Newfield or Encana are contractually obligated to pay,
would still be paid regardless of the outcome of the advisory (non-binding) vote on the non-binding compensation advisory proposal.



Proposal 3the Newfield adjournment proposal.The affirmative vote of a
majority of votes cast by holders of the issued and outstanding shares of Newfield common stock entitled to vote thereon and present in person or represented by proxy at the Newfield special meeting.

As of the record date, there were 200,933,274 shares of Newfield common stock outstanding. As of the record date, Newfield directors and
executive officers, as a group, beneficially owned and were entitled to vote 1,715,316 shares of Newfield common stock or approximately 0.9% of the issued and outstanding shares of Newfield common stock.

The Merger (see page 61)

Upon satisfaction or waiver of the conditions to closing in the merger agreement, on the closing date, Merger Sub, an indirect wholly-owned
subsidiary of Encana formed for the purpose of effecting the merger, will merge with and into Newfield, whereby Newfield will be the surviving company in the merger as an indirect wholly-owned subsidiary of Encana. At the effective time of the
merger, each share of Newfield common stock issued and outstanding immediately prior to the effective time (other than excluded shares) will be cancelled and

15

converted into the right to receive 2.6719 Encana common shares with cash paid in lieu of the issuance of fractional Encana common shares, if any. In addition, Newfield will take all actions as
may be necessary so that at the effective time, each outstanding restricted stock award, time-based restricted stock unit award, performance-based restricted stock unit award and share of notional stock in respect of Newfield common stock will be
treated as described in The MergerTreatment of Newfield Equity Awards in the Merger.

Recommendation of the
Encana Board and Reasons for the Merger (see page 73)

In the course of reaching its decision to approve the merger agreement and the transactions contemplated by the merger agreement, including
the share issuance, the Encana board considered a number of factors in its deliberations. For a more complete discussion of these factors, see The MergerRecommendation of the Encana Board and Reasons for the Merger.

Recommendation of the Newfield Board and Reasons for the Merger (see page 77)

In the course of reaching its decision to approve the merger agreement and the transactions contemplated by the merger agreement, including
the merger, the Newfield board considered a number of factors in its deliberations. For a more complete discussion of these factors, see The MergerRecommendation of the Newfield Board and Reasons for the Merger.

Opinions of Encanas Financial Advisors (see page 88)

Opinion of Credit Suisse

On
October 31, 2018, Credit Suisse Securities (Canada) Inc. (Credit Suisse) rendered its oral opinion to the Encana board (which was subsequently confirmed in writing by delivery of Credit Suisses written opinion addressed to the
Encana board dated the same date) as to, as of October 31, 2018, the fairness, from a financial point of view, to Encana of the exchange ratio in the merger pursuant to the merger agreement.

Credit Suisses opinion was directed to the Encana board (in its capacity as such), and only addressed the fairness, from a financial
point of view, to Encana of the exchange ratio in the merger pursuant to the merger agreement and did not address any other aspect or implication (financial or otherwise) of the merger. The summary of Credit Suisses opinion in this joint proxy
statement/prospectus is qualified in its entirety by reference to the full text of its written opinion, which is included as Annex B to this joint proxy statement/prospectus and sets forth the procedures followed, assumptions made, qualifications
and limitations on the review undertaken and other matters considered by Credit Suisse in preparing its opinion. However, neither Credit Suisses written opinion nor the summary of its opinion and the related analyses set forth in this joint
proxy statement/prospectus are intended to be, and they do not constitute, advice or a recommendation to any securityholder as to how such holder should vote or act on any matter relating to the merger.

For further information, see the section of this joint proxy statement/prospectus entitled The MergerOpinions of Encanas
Financial Advisors  Opinion of Credit Suisse and Annex B to this joint proxy statement/prospectus.

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Opinion of TD Securities

On October 31, 2018, at a meeting of the Encana board, TD Securities Inc. (TD Securities) rendered its oral opinion to the
Encana board (which was subsequently confirmed in writing by delivery of TD Securities written opinion addressed to the Encana board dated the same date) that, as of that date and based on and subject to the matters considered, the procedures
followed, the assumptions made and various limitations of, and qualifications to, the review undertaken by TD Securities as set forth in its written opinion, the exchange ratio was fair, from a financial point of view, to Encana.

The full text of the written opinion of TD Securities to the Encana board, dated as of October 31, 2018, is attached as Annex C to
this joint proxy statement/prospectus and is incorporated herein by reference in its entirety. The summary of the opinion of TD Securities in this joint proxy statement/prospectus is qualified in its entirety by reference to the full text of the
opinion. Encana shareholders should read TD Securities opinion and the summary of TD Securities opinion carefully and in their entirety for a discussion of the matters considered, the procedures followed, the assumptions made and various
limitations of, and qualifications to, the review undertaken by TD Securities in rendering its opinion.

TD Securities
opinion was provided to the Encana board (in its capacity as such) for its information in connection with its consideration of the merger. TD Securities opinion does not constitute a recommendation to the Encana board with respect to the
merger, nor does TD Securities opinion constitute advice or a recommendation to any Encana shareholder or Newfield stockholder as to how to vote with respect to the merger and does not in any manner address the prices at which Encana common
shares will trade at any time. TD Securities opinion addresses only the fairness to Encana, from a financial point of view and as of the date of such opinion, of the exchange ratio pursuant to the merger agreement and does not address any
terms or other aspects of the merger or any other matter.

For further information, see the section of this joint proxy
statement/prospectus entitled The MergerOpinions of Encanas Financial AdvisorsOpinion of TD Securities and Annex C to this joint proxy statement/prospectus.

Opinion of Newfields Financial Advisor (see page 106)

On October 31, 2018, at a meeting of the Newfield board, J.P. Morgan Securities LLC (J.P. Morgan) rendered its oral opinion to
the Newfield board (which was subsequently confirmed in writing by delivery of J.P. Morgans written opinion addressed to the Newfield board dated the same date) that, as of such date and based upon and subject to the factors and
assumptions set forth in its opinion, the exchange ratio in the proposed merger was fair, from a financial point of view, to Newfield stockholders. J.P. Morgan has confirmed its October 31, 2018 oral opinion by delivering its written opinion to
the Newfield board, dated October 31, 2018, that, as of such date, the exchange ratio in the proposed merger was fair, from a financial point of view, to Newfield stockholders.

The full text of the written opinion of J.P. Morgan dated October 31, 2018, which sets forth the assumptions made, matters considered
and limits on the review undertaken, is attached as Annex D to this joint proxy statement/prospectus and is incorporated herein by reference. The summary of the opinion of J.P. Morgan set forth in this joint proxy statement/prospectus is qualified
in its entirety by reference to the full text of such opinion. Newfield stockholders are urged to read the opinion in its entirety. J.P. Morgans written opinion was addressed to the Newfield board (in its capacity as such) in connection with
and for the purposes of its evaluation of the proposed merger, was directed only to the exchange ratio in the proposed merger and did not address any other aspect of the proposed merger. J.P. Morgan expressed no opinion as to the fairness of the
exchange ratio to the holders of any other class of securities, creditors or other constituencies of Newfield or as to the underlying decision by Newfield to engage in the proposed

17

merger. The issuance of J.P. Morgans opinion was approved by a fairness committee of J.P. Morgan. The opinion does not constitute a recommendation to any Newfield stockholder as to how such
stockholder should vote with respect to the proposed merger or any other matter.

For further information, see the section of this
joint proxy statement/prospectus entitled The MergerOpinion of Newfields Financial Advisor and Annex D to this joint proxy statement/prospectus.

In considering the recommendation of the Newfield board that Newfield stockholders vote to approve the merger agreement proposal, the non-binding compensation advisory proposal and the Newfield adjournment proposal, Newfield stockholders should be aware that aside from their interests as stockholders of Newfield, Newfields directors and
executive officers have interests in the merger that may be different from, or in addition to, the interests of Newfield stockholders generally. The Newfield board was aware of and considered these potential interests, among other matters, in
evaluating and negotiating the merger agreement and the transactions contemplated therein, in approving the merger and in recommending the approval of the merger agreement proposal, the non-binding
compensation advisory proposal and the Newfield adjournment proposal. See The MergerBackground of the Merger and The MergerRecommendation of the Newfield Board and Reasons for the Merger beginning on page 77.
Newfield stockholders should take these interests into account in deciding whether to vote FOR the merger agreement proposal and the other proposals. These interests are described in more detail below, and certain of them are quantified
in the narrative and the tables below. For the purposes of the plans and agreements described herein, to the extent applicable, the completion of the merger will constitute a change of control, change in control or term of similar meaning.

Board of Directors and Management of Encana Following Completion of the Merger (see page 122)

In connection with the merger, Encana and Newfield have agreed that two (2) members of the Newfield board (the Newfield
Designees), to be mutually agreed by Encana and Newfield, will be appointed to the Encana board immediately after the effective time of the merger. Additionally, from the closing of the merger until immediately following the first annual
meeting of Encana shareholders that occurs after the closing of the merger, Encana shall take necessary action to cause the Newfield Designees, or individuals designated by the Newfield Designees, to be appointed to the Encana board as more fully
described in the merger agreement; provided, however, that the Newfield Designees must be reasonably acceptable to the nominating and corporate governance committee of the Encana board and the Encana board, as a whole. Encana and Newfield expect
that the Newfield Designees will be Steven W. Nance and Thomas G. Ricks.

Upon completion of the merger, the current directors and
executive officers of Encana are expected to continue in their current positions, other than as may be publicly announced by Encana in the normal course.

No Dissenters or Appraisal Rights (see page 60)

No dissenters or appraisal rights will be available with respect to the merger.

Material U.S. Federal Income Tax Consequences of the Merger (see page 122)

The exchange of Newfield common stock for Encana common shares pursuant to the merger will be a taxable transaction for U.S. federal income tax
purposes and may also be taxable under state and local and other tax laws. In general, a U.S. holder of Newfield common stock that receives Encana common shares in connection with the merger will recognize gain or loss equal to the difference, if
any, between (1) the fair market value of the Encana common shares received and (2) such U.S. holders adjusted tax basis in its shares of Newfield common stock exchanged. The deductibility of loss, if any, of a U.S. holder of
Newfield common stock as a result of the merger may be subject to limitation for U.S. federal income tax purposes. A U.S. holder of Newfield common stock will be subject to U.S. federal income tax on any gain recognized without a corresponding
receipt of cash. You should read the section entitled The MergerMaterial U.S. Federal Income Tax Consequences of

18

the Merger. You are urged to consult your tax advisors regarding the U.S. federal income tax consequences of the merger to you in your particular circumstances, as well as tax consequences
arising under the laws of any state, local or foreign taxing jurisdiction.

Accounting Treatment (see page 133)

Encana prepares its financial statements in accordance with generally accepted accounting principles in the United States
(GAAP). The merger will be accounted for using the acquisition method of accounting with Encana being considered the acquirer of Newfield for accounting purposes. This means that Encana will record all assets acquired and liabilities
assumed from Newfield at their acquisition date fair values at the effective date of the merger. Any excess of the consideration transferred over the fair value amounts of the identifiable assets acquired net of liabilities assumed is recorded as
goodwill. Goodwill is assessed for impairment at least annually.

Regulatory Approvals Required to Complete the Merger (see
page 134)

The completion of the merger is subject to antitrust review in the United States. Under the Hart-Scott-Rodino Antitrust
Improvements Act of 1976, as amended (the HSR Act), and the rules promulgated thereunder, the merger cannot be completed until the parties to the merger agreement have given notification and furnished information to the Federal Trade
Commission (the FTC) and the United States Department of Justice (the DOJ), and until the applicable waiting period has expired or has been terminated.

On November 15, 2018, Encana and Newfield each filed a premerger notification and report form under the HSR Act and on November 21,
2018, the FTC granted early termination under the HSR Act.

In connection with the share issuance proposal, Encana has filed a
registration statement with the SEC under the Exchange Act that must be declared effective by the SEC.

In addition, the completion of the
merger is subject to approval for listing of the Encana common shares issued in the merger on the NYSE, subject to official notice of issuance, and the TSX, subject to satisfaction of customary listing conditions of the TSX.

Treatment of Newfield Equity Awards in the Merger (see page 134)

Pursuant to the merger agreement, the following will occur at the effective time:

Restricted Stock Awards: All outstanding Newfield restricted stock awards will be cancelled and each holder of Newfield restricted stock
will be entitled to receive, on a fully vested basis, for each share of restricted stock subject to any such award, the merger consideration.

Time-Based Restricted Stock Units with a Cash Settlement Feature: All outstanding Newfield time-based restricted stock units with a cash
settlement feature will be cancelled and each holder of such restricted stock units will be entitled to receive, on a fully vested basis, for each such restricted stock unit, a cash payment of equivalent value to the merger consideration, based on
the volume weighted averages of the trading price of Encana common shares on each of the five consecutive trading days ending on the trading day that is three trading days prior to the effective time of the merger.

Time-Based Restricted Stock Units with a Stock Settlement Feature: All outstanding Newfield time-based restricted stock units with a
stock settlement feature will be cancelled and each holder of such restricted stock units will be entitled to receive, on a fully vested basis, for each such restricted stock unit, the merger consideration.

Performance-Based Restricted Stock Units: All outstanding Newfield performance-based restricted stock units will be cancelled and will
convert into the right to receive the merger consideration, with the

19

performance-based vesting conditions applicable to such Newfield performance-based restricted stock units deemed achieved based on the determination of the
Newfield compensation committee, not to exceed 200% per Newfield performance-based restricted stock unit.

Notional Stock: Any
shares of Newfield notional stock held in connection with Newfields Nonqualified Deferred Compensation Plan will convert into the right to receive a cash payment of equivalent value to the merger consideration, based on the volume weighted
averages of the trading price of Encana common shares on each of the five consecutive trading days ending on the trading day that is three trading days prior to the effective time of the merger.

For additional information regarding the treatment of Newfield equity awards, see the section entitled The MergerTreatment of
Newfield Equity Awards in the Merger beginning on page 134.

Listing of Encana Common Shares; Delisting and
Deregistration of Newfield Common Stock (see page 135)

It is a condition to the consummation of the merger that the Encana
common shares to be issued to Newfield stockholders in connection with the merger be authorized for listing on the NYSE, subject to official notice of issuance, and the TSX, subject to satisfaction of customary listing conditions of the TSX. Shares
of Newfield common stock currently trade on the NYSE under the stock symbol NFX. When the merger is completed, the Newfield common stock currently listed on the NYSE will cease to be traded on the NYSE and will be deregistered under the
Exchange Act. This will make certain provisions of the Exchange Act, such as the requirement of furnishing a proxy or information statement in connection with stockholder meetings, no longer applicable to Newfield.

No Solicitation of Alternative Proposals (see page 145)

The merger agreement precludes Encana and Newfield from soliciting, initiating or knowingly encouraging or facilitating (including by way of
providing information or taking any other action) or continuing discussions or negotiations with any person with respect to any proposal for a competing transaction, including the acquisition of a significant interest in Encanas or
Newfields capital stock or assets. However, if prior to the receipt of the requisite Encana shareholder approval or Newfield stockholder approval, as applicable, Encana or Newfield receives an unsolicited bona fide written acquisition proposal
from a third party for a competing transaction that did not result from a knowing and intentional breach of the non-solicitation obligations set forth in the merger agreement and that the Encana board or the
Newfield board, as applicable, among other things, determines in good faith (after consultation with its outside legal and financial advisors) constitutes or would reasonably be expected to result in a proposal that is superior to the merger, then
Encana or Newfield, as applicable, may furnish non-public information to and enter into discussions with, and only with, that third party and its representatives about such competing transaction.

For a more detailed discussion on Encana and Newfield and the ability of their boards of directors to consider other proposals, see the
section entitled The Merger AgreementNo Solicitation of Alternative Proposals.

Conditions to Completion
of the Merger (see page 151)

The obligations of Encana and Newfield to consummate the merger are subject to the satisfaction or waiver
(to the extent permissible under applicable laws) of the following mutual conditions:



approval of the merger agreement proposal by Newfield stockholders and approval of the share issuance proposal by
Encana shareholders;

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

absence of any judgment, settlement, order, decision, writ, injunction, decree, stipulation or legal or
arbitration award of, or promulgated or issued by, any governmental entity (whether temporary, preliminary or permanent) or law, in each case, that is in effect as of immediately prior to the effective time, and has the effect of restraining,
enjoining or otherwise prohibiting the consummation of the merger;



any waiting period (and extensions thereof) applicable to the merger under the HSR Act shall have been terminated
or expired;



the registration statement on Form S-4 filed by Encana in connection with
the share issuance shall have been declared effective under the Securities Act and shall not be the subject of any stop order or proceeding seeking a stop order; and



Encana common shares issued in the merger having been approved for listing on the NYSE, subject to official
notice of issuance, and the TSX, subject to satisfaction of customary listing conditions of the TSX.

The obligation of
Newfield to effect the merger is also subject to the satisfaction or waiver by Newfield of the following additional conditions:



the accuracy of the representations and warranties of Encana and Merger Sub set forth in the merger agreement,
subject to the materiality standards set forth in the merger agreement, as of the date of the merger agreement and as of the closing date of the merger (except to the extent such representations and warranties are expressly made as of a specific
date, in which case such representations and warranties will be true and correct as of such specific date only), and Newfields receipt of an officers certificate from Encana to such effect; and



performance of, or compliance with, in all material respects all obligations, covenants and agreements required
to be performed or complied with under the merger agreement by Encana and Merger Sub at or prior to the effective time and Newfields receipt of an officers certificate from Encana to such effect.

The obligations of Encana and Merger Sub to effect the merger are also subject to the satisfaction or waiver by Encana of the following
additional conditions:



the accuracy of the representations and warranties of Newfield set forth in the merger agreement, subject to the
materiality standards set forth in the merger agreement, as of the date of the merger agreement and as of the closing date of the merger (except to the extent such representations and warranties are expressly made as of a specific date, in which
case such representations and warranties will be true and correct as of such specific date only), and Encanas receipt of an officers certificate from Newfield to such effect; and



performance of, or compliance with, in all material respects all obligations, covenants and agreements required
to be performed or complied with under the merger agreement by Newfield at or prior to the effective time and Encanas receipt of an officers certificate from Newfield to such effect.

As further discussed under the section entitled Risk Factors, neither Encana nor Newfield can be certain when, or if, the
conditions to the merger will be satisfied or waived, or that the merger will be completed.

Termination of the Merger
Agreement (see page 152)

Encana and Newfield may mutually agree to terminate the merger agreement before consummating the merger,
even after approval of the merger agreement proposal by Newfield stockholders and approval of the share issuance proposal by Encana shareholders.

21

In addition, either Encana or Newfield may terminate the merger agreement if:



(i) prior to the consummation of the merger, the terminating party is not then in material breach of any of
its representations, warranties, covenants or agreements under the merger agreement, (ii) any of the representations and warranties of the non-terminating party shall have become inaccurate as of a date
subsequent to the date of the merger agreement (as if made on such subsequent date) or the non-terminating party shall have breached, failed to perform or violated its respective covenants or agreements, in
each case such that a condition to effect the merger would not be satisfied, and (iii) in the case of clause (ii), such breach, failure to perform, violation or inaccuracy is not capable of being cured by June 30, 2019 (the
outside date) or, if capable of being cured by the outside date, is not cured by the non-terminating party, before the earlier of (x) the business day immediately prior to the outside date and
(y) the 30th calendar day following receipt of written notice from the terminating party of such breach, failure to perform, violation or inaccuracy;



the consummation of the merger has not occurred on or before the outside date; provided that the right to
terminate shall not be available to any party whose material breach of any provision of the merger agreement has been the cause of, or resulted in, the failure of the consummation of the merger to occur on or before the outside date;



after the final adjournment or postponement of the Encana special meeting or the Newfield special meeting, if the
required Encana shareholder or Newfield stockholder approval, as applicable, has not been obtained; or



a governmental entity of competent jurisdiction with a material connection to any party, its subsidiaries or its
respective assets has issued a final, non-appealable order permanently restraining, enjoining or otherwise prohibiting the consummation of the transactions contemplated by the merger agreement, including the
merger; provided that the right to terminate the merger agreement shall not be available to any party whose failure to comply with certain obligations with respect to such order under the merger agreement or whose material breach of the merger
agreement has been the cause of or resulted in, the issuance of such final, non-appealable order.

In addition, the merger agreement may be terminated under the following circumstances:



by Encana, prior to the time the Newfield stockholder approval is obtained, if (i) the Newfield board has
effected a change of recommendation (provided that Encana is only entitled to terminate the merger agreement for ten (10) business days following the date a change of recommendation occurs) or (ii) Newfield has violated or breached (or is
deemed pursuant to the terms thereof, to have violated or breached) in any material respect any of its non-solicitation obligations;



by Newfield, prior to the time the Encana shareholder approval is obtained, if (i) the Encana board has
effected a change of recommendation (provided that Newfield is only entitled to terminate the merger agreement for ten (10) business days following the date a change of recommendation occurs) or (ii) Encana has violated or breached (or is
deemed pursuant to the terms thereof, to have violated or breached) in any material respect any non-solicitation obligation;



by Newfield, prior to the time the Newfield stockholder approval is obtained, in order to effect a change of
recommendation and substantially concurrently enter into an acquisition agreement providing for a superior proposal that did not result from a material breach of its non-solicitation obligations; provided that
(i) Newfield has complied with certain provisions of its non-solicitation obligations and (ii) immediately prior to or substantially concurrently with (and as a condition to) the termination,
Newfield pays to Encana the applicable termination fee; or



by Encana, prior to the time the Encana shareholder approval is obtained, in order to effect a change of
recommendation and substantially concurrently enter into an acquisition agreement providing for a

22

superior proposal that did not result from a material breach of its non-solicitation obligations; provided that (i) Encana has complied with certain
provisions of its non-solicitation obligations and (ii) immediately prior to or substantially concurrently with (and as a condition to) the termination, Encana pays to Newfield the applicable termination
fee.

Expenses and Termination Fees Relating to the Termination of the Merger Agreement (see
page 153)

Termination Fees Payable by Encana

The merger agreement requires Encana to pay Newfield a termination fee of $300 million if:



(i) Encana terminates the merger agreement because the effective time has not occurred by the outside date at a
time when Newfield would be permitted to terminate the merger agreement or (ii) Newfield terminates the merger agreement, in each case because Encana has violated or breached (or is deemed pursuant to the terms thereof, to have violated or
breached) in any material respect its non-solicitation obligations under the merger agreement and (A) at any time on or after the date of the merger agreement and prior to such termination an acquisition
proposal shall have been made to the Encana board or Encana or publicly announced or publicly known and, in either case, not withdrawn at the time of the Encana shareholders meeting, and (B) within twelve (12) months after the date of such
termination, Encana enters into a definitive agreement providing for an acquisition proposal or any acquisition proposal is consummated;



Newfield terminates the merger agreement due to a change of recommendation by Encana;



Encana terminates the merger agreement due to a superior proposal for Encana; or



either party terminates the merger agreement after the final adjournment or postponement of the Encana special
meeting following a change of recommendation by Encana and Encana shareholder approval has not been obtained.

In no
event shall Encana be required to pay the termination fee on more than one occasion.

Termination Fees Payable by Newfield

The merger agreement requires Newfield to pay Encana a termination fee of $150 million if:



(i) Newfield terminates the merger agreement because the effective time has not occurred by the outside date at a
time when Encana would be permitted to terminate the merger agreement or (ii) Encana terminates the merger agreement, in each case because Newfield has violated or breached (or is deemed pursuant to the terms thereof, to have violated or
breached) in any material respect its non-solicitation obligations under the merger agreement and (A) at any time on or after the date of the merger agreement and prior to such termination an acquisition
proposal shall have been made to the Newfield board or Newfield or publicly announced or publicly known and, in either case, not withdrawn at the time of the Newfield stockholders meeting, and (B) within twelve (12) months after the date
of such termination, (x) Newfield enters into a definitive agreement providing for an acquisition proposal or (y) any acquisition proposal is consummated;



Encana terminates the merger agreement due to a change of recommendation by Newfield;



Newfield terminates the merger agreement due to a superior proposal for Newfield; and



either party terminates the merger agreement after the final adjournment or postponement of the Newfield special
meeting following a change of recommendation by Newfield and Newfield stockholder approval has not been obtained.

In no
event shall Newfield be required to pay the termination fee on more than one occasion.

23

Expenses

In addition, unless otherwise entitled to a termination fee, either Encana or Newfield will be obligated to pay the other party an expense
reimbursement fee of $50 million in connection with a termination under certain circumstances related to the failure to obtain Newfield stockholder approval or Encana shareholder approval, as applicable, or to achieve certain conditions to
consummate the merger. In no event will either party be required to pay an expense reimbursement fee on more than one occasion.

If either
party pays a termination fee, then such party will not be required to also pay an expense reimbursement fee. Further, any payment of an expense reimbursement fee may be deducted from any subsequent payment of a termination fee.

Specific Performance (see page 155)

In addition to any other remedy that may be available to each party, including monetary damages, prior to the valid termination of the merger
agreement, each of the parties will be entitled to an injunction or injunctions, or any other appropriate form of specific performance or equitable relief, to prevent or remedy any breaches or threatened breaches of the merger agreement by any other
party and to enforce specifically its terms and provisions.

Completion of the Merger (see page 137)

The merger is expected to be completed in the first quarter of 2019. However, neither Encana nor Newfield can predict the actual date on which
the merger will be completed, nor can the parties ensure that the merger will be completed, because completion is subject to conditions beyond each partys control.

Newfield stockholders receiving Encana common shares in connection with the merger will have different rights once they become shareholders of
Encana due to differences between laws of Canada and the State of Delaware and the governing corporate documents of Encana and Newfield. These differences are described in more detail under Comparison of Rights of Encana Shareholders and
Newfield Stockholders.

Risk Factors (see page 39)

Before voting at the Newfield special meeting or the Encana special meeting, you should carefully consider all of the information contained in
or incorporated by reference into this joint proxy statement/prospectus, including the specific factors under the heading Risk Factors.

24

SELECTED HISTORICAL CONSOLIDATED FINANCIAL DATA OF ENCANA

The following table sets forth selected historical consolidated financial data that has been derived from Encanas audited
consolidated financial statements as of and for the years ended December 31, 2017, 2016, 2015, 2014 and 2013, as well as from Encanas unaudited consolidated financial statements as of and for the nine months ended September 30, 2018
and 2017, and the related notes thereto. This disclosure does not include the effects of the merger. The information set forth below is only a summary and is not necessarily indicative of the results of future operations of Encana or the combined
company, and the following information should be read in conjunction with, and is qualified in its entirety by, Encanas consolidated financial statements, the related notes thereto and Managements Discussion and Analysis of
Financial Condition and Results of Operations contained in Encanas Annual Report on Form 10-K for the year ended December 31, 2017 and Quarterly Report on Form
10-Q for the quarterly period ended September 30, 2018, each of which are incorporated by reference into this joint proxy statement/prospectus. The selected statement of earnings data for the years ended
December 31, 2014 and 2013 and selected balance sheet data as of December 31, 2015, 2014 and 2013 have been derived from Encanas audited consolidated financial statements for such years, which have not been included or incorporated
by reference into this joint proxy statement/prospectus. The selected balance sheet data as of September 30, 2017 has been derived from Encanas unaudited consolidated financial statements as of September 30, 2017, which have not been
included or incorporated by reference into this joint proxy statement/prospectus. For more information, see Where You Can Find More Information beginning on page 196.

Nine MonthsEndedSeptember 30

Year EndedDecember 31

($ millions, unless otherwise specified)

2018

2017

2017

2016

2015

2014

2013

Statement of Earnings Data

Revenues

4,025

2,751

4,443

2,918

4,422

8,019

5,858

Impairments







1,396

6,473



21

Operating Income (Loss)

340

806

1,068

(1,881

)

(6,301

)

2,331

870

Gain (Loss) on Divestitures, Net

4

405

404

390

14

3,426

7

Net Earnings (Loss) Attributable to Common Shareholders

39

1,056

827

(944

)

(5,165

)

3,392

236

Per Share Data

Net Earnings (Loss) per Common Share Basic & Diluted

0.04

1.09

0.85

(1.07

)

(6.28

)

4.58

0.32

Dividends Declared per Common Share

0.045

0.045

0.06

0.06

0.28

0.28

0.67

Weighted Average Common Shares Outstanding Basic & Diluted (millions)

962.2

973.1

973.1

882.6

822.1

741.0

737.7

Balance Sheet Data

Cash and Cash Equivalents

615

889

719

834

271

338

2,566

Total Assets

15,318

15,164

15,267

14,653

15,614

24,492

17,599

Capital Lease Obligations and The Bow Office Building

1,526

1,669

1,639

1,570

1,591

1,959

2,175

Long-Term Debt, Including Current Portion

4,198

4,197

4,197

4,198

5,333

7,301

7,078

Total Shareholders Equity

6,494

6,965

6,728

6,126

6,167

9,685

5,147

Statement of Cash Flow Data

Cash From (Used In) Operating Activities

1,741

681

1,050

625

1,681

2,667

2,289

Non-GAAP Cash Flow (1)

1,575

899

1,343

838

1,430

2,934

2,581

Capital Expenditures

1,626

1,287

1,796

1,132

2,232

2,526

2,712

Net Acquisitions & (Divestitures)

(72

)

(660

)

(682

)

(1,052

)

(1,838

)

(1,329

)

(521

)

25

(1)

Non-GAAP Cash Flow is a
non-GAAP measure and has no standardized meaning under GAAP. It is used by Encanas management and investors to help assist in measuring Encanas ability to finance capital programs and meet
financial obligations. It is not intended to replace Cash From (Used In) Operating Activities as a measure. For the definition of Non-GAAP Cash Flow and a reconciliation of
Non-GAAP Cash Flow to Cash Flow From (Used In) Operating Activities see Non-GAAP Financial Measures below.

Non-GAAP Financial Measures

Non-GAAP Cash Flow is a non-GAAP measure defined as cash from
(used in) operating activities excluding net change in other assets and liabilities, net change in non-cash working capital and current tax on sale of assets.

Encanas management believes this measure is useful to Encana and its investors as a measure of operating and financial performance
across periods and against other companies in the industry, and is an indication of Encanas ability to generate cash to finance capital programs, to service debt and to meet other financial obligations. This measure is used, along with other
measures, in the calculation of certain performance targets for Encanas management and employees.

Encana has included a
reconciliation of Non-GAAP Cash Flow to Cash Flow From (Used In) Operating Activities, the most directly comparable GAAP financial measure, below for the periods indicated:

Nine MonthsEndedSeptember 30

Year EndedDecember 31

($ millions)

2018

2017

2017

2016

2015

2014

2013

Cash From (Used in) Operating Activities

1,741

681

1,050

625

1,681

2,667

2,289

(Add back) deduct:

Net change in other assets and liabilities

(33

)

(27

)

(40

)

(26

)

(11

)

(43

)

(80

)

Net change in non-cash working capital

199

(191

)

(253

)

(187

)

262

(9

)

(179

)

Current tax on sale of assets











(215

)

(33

)

Non-GAAP Cash Flow

1,575

899

1,343

838

1,430

2,934

2,581

26

SELECTED HISTORICAL CONSOLIDATED FINANCIAL DATA OF NEWFIELD

The following table sets forth selected historical consolidated financial data from Newfields audited consolidated financial
statements as of and for the years ended December 31, 2017, 2016, 2015, 2014 and 2013, as well as from Newfields unaudited consolidated financial statements as of and for the nine months ended September 30, 2018 and 2017, and the
related notes thereto. This disclosure does not include the effects of the merger. The information set forth below is only a summary and is not necessarily indicative of the results of future operations of Newfield or the combined company, and the
following information should be read in conjunction with, and is qualified in its entirety by, Newfields consolidated financial statements, the related notes thereto and Managements Discussion and Analysis of Financial Condition
and Results of Operations contained in Newfields Annual Report on Form 10-K for the year ended December 31, 2017 and Quarterly Report on Form 10-Q for
the quarterly period ended September 30, 2018, each of which are incorporated by reference into this joint proxy statement/prospectus. The selected statement of operations data for the years ended December 31, 2014 and 2013 and selected
balance sheet data as of December 31, 2015, 2014 and 2013 have been derived from Newfields audited consolidated financial statements for such years, which have not been included or incorporated by reference into this joint proxy
statement/prospectus. The selected balance sheet data as of September 30, 2017 has been derived from Newfields unaudited consolidated financial statements as of September 30, 2017, which have not been included or incorporated by
reference into this joint proxy statement/prospectus. For more information, see Where You Can Find More Information beginning on page 196.

Nine MonthsEndedSeptember 30

Year EndedDecember 31

($ millions, except per share data)

2018

2017

2017

2016

2015

2014

2013

Results of Operations

Oil, gas and NGL revenues(1)

1,965

1,257

1,767

1,472

1,557

2,288

1,857

Income (loss) from continuing operations

429

332

427

(1,230

)

(3,362

)

650

73

Net income (loss)

429

332

427

(1,230

)

(3,362

)

900

147

Earnings (loss) per share

Diluted

Income (loss) from continuing operations

2.14

1.66

2.13

(6.36

)

(21.18

)

4.71

0.39

Earnings (loss) per share

2.14

1.66

2.13

(6.36

)

(21.18

)

6.52

0.94

Weighted average number of shares outstanding (for diluted earnings (loss) per share)

201

200

200

193

159

138

136

Balance Sheet (at end of period)

Total assets

5,676

4,744

4,961

4,312

4,768

9,580

9,297

Long-term debt

2,436

2,433

2,434

2,431

2,467

2,874

3,670

(1)

Continuing operations only (excludes Malaysia, which was sold in February 2014).

27

SELECTED UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL DATA

The following selected unaudited pro forma condensed combined consolidated statements of earnings data for the nine months ended
September 30, 2018 and year ended December 31, 2017 have been prepared to give effect to the merger as if the merger had been completed on January 1, 2017. The unaudited pro forma condensed combined consolidated balance sheet data at
September 30, 2018 have been prepared to give effect to the merger as if the merger was completed on September 30, 2018. The following selected unaudited pro forma condensed combined consolidated financial information should be read in
conjunction with the section entitled Unaudited Pro Forma Condensed Combined Financial Statements and related notes included in this joint proxy statement/prospectus beginning on page 156.

The pro forma financial statements have been prepared using the acquisition method of accounting for business combinations under GAAP, with
Encana treated as the acquirer. Under the acquisition method of accounting, Encana will record all assets acquired and liabilities assumed at their respective acquisition date fair values at the effective time of closing of the merger. The
acquisition method of accounting is dependent upon certain valuations and other studies that have yet to commence or progress to a stage where there is sufficient information for a definitive measure. The sources and amounts of merger transaction
expenses may also differ from that assumed in the following pro forma adjustments. Accordingly, the pro forma adjustments are preliminary, have been made solely for the purpose of providing pro forma financial statements, and are subject to revision
based on a final determination of fair values as of the date of acquisition. Differences between these preliminary estimates and the final acquisition accounting may have a material impact on the accompanying pro forma financial statements and the
combined companys future results of operations and financial position.

The unaudited pro forma condensed combined financial
statements are provided for illustrative purposes only and are not intended to represent or be indicative of the results of operations or financial position of the combined company that would have been recorded had the merger been completed as of
the dates presented and should not be taken as representative of future results of operations or financial position of the combined company. The unaudited pro forma condensed combined financial statements do not reflect the impacts of any potential
operational efficiencies, asset dispositions, cost savings or economies of scale that the combined company may achieve with respect to the combined operations. Future results may vary significantly from the results reflected because of various
factors, including those described in the section of this joint proxy statement/prospectus entitled Risk Factors, in Item 1A Risk Factors of Encanas Annual Report for the fiscal year ended December 31, 2017 on Form 10-K incorporated by reference in this joint proxy statement/prospectus, in Item 1A Risk Factors of Encanas Quarterly Report for the quarterly period ended September 30, 2018 on Form 10-Q incorporated by reference in this joint proxy statement/prospectus and in Item 1A Risk Factors of Newfields Annual Report for the fiscal year ended December 31, 2017 on Form 10-K incorporated by reference in this joint proxy statement/prospectus.

Nine Months EndedSeptember 30, 2018

Year EndedDecember 31, 2017

($ millions, unless otherwise specified)

Pro Forma Statements of Earnings Data

Total Revenues

5,215

6,163

Net Earnings (Loss)

427

1,007

Net Earnings (Loss) per Common Share Basic & Diluted

0.28

0.66

28

($ millions, unless otherwise specified)

As ofSeptember 30, 2018

Pro Forma Balance Sheet Data

Cash and Cash Equivalents

873

Total Assets

23,081

Long-Term Debt, Including Current Portion

6,773

Shareholders Equity

10,285

29

PRO FORMA COMBINED OIL AND NATURAL GAS RESERVE AND PRODUCTION
DATA

The following table presents selected unaudited pro forma information regarding Encanas proved reserves as of
December 31, 2017 after giving effect to the acquisition of Newfields proved reserves as if they were acquired on January 1, 2017. The following estimates of the net proved oil and natural gas reserves of Encanas oil and gas
properties as of December 31, 2017 are based on evaluations prepared by Encanas internal qualified reserves evaluators. In 2017, McDaniel & Associates Consultants Ltd. (McDaniel) audited 75% of Encanas estimated
Canadian proved reserve volumes and Netherland, Sewell & Associates, Inc. (NSAI) audited 80% of Encanas estimated U.S. proved reserve volumes. The following estimates of the net proved oil and natural gas reserves of
Newfields oil and gas properties are as of December 31, 2017 and were prepared by Newfields petroleum engineering staff. Ryder Scott Company (Ryder Scott) and DeGolyer and MacNaughton (D&M) performed
audits of the internally prepared reserve estimates on certain fields aggregating to 97% of 2017 year-end reported proved reserve volumes on a barrel of oil equivalent basis. All reserves information presented
herein was prepared in accordance with applicable SEC regulations. See Cautionary Note Regarding Oil and Gas Reserve Estimates beginning on page 36.

There are numerous uncertainties inherent in estimating quantities and values of proved reserves and in projecting future rates of production
and the amount and timing of development expenditures, including many factors beyond the property owners control. The following reserve data represents estimates only and should not be construed as being precise. The assumptions used in
preparing these estimates may not be realized, causing the quantities of oil and gas that are ultimately recovered, the timing of the recovery of oil and gas reserves, the production and operating costs incurred and the amount and timing of future
development expenditures to vary from the estimates presented herein. Actual production, revenues and expenditures with respect to reserves will vary from estimates and the variances may be material.

These estimates were calculated using the 12-month average of the first day of the month reference
prices as adjusted for location and quality differentials. Any significant price changes will have a material effect on the quantity and present value of the reserves. These estimates depend on a number of variable factors and assumptions, including
historical production from the area compared with production from other comparable producing areas, the assumed effects of regulations by governmental agencies, assumptions concerning future oil and gas prices, and assumptions concerning future
operating costs, transportation costs, severance and excise taxes, development costs and workover and remedial costs.

The following
estimated pro forma combined net proved developed and undeveloped oil, NGL and natural gas reserves is not necessarily indicative of the results that might have occurred had the merger been completed on January 1, 2017 and is not intended to be
a projection of future results. Future results may vary significantly from the results reflected because of various factors, including those described in the section of this joint proxy statement/prospectus entitled Risk Factors, in Item
1A Risk Factors of Encanas Annual Report for the fiscal year ended December 31, 2017 on Form 10-K incorporated by reference in this joint proxy statement/prospectus, in Item 1A Risk Factors of
Encanas Quarterly Report for the quarterly period ended September 30, 2018 on Form 10-Q incorporated by reference in this joint proxy statement/prospectus and in Item 1A Risk Factors of
Newfields Annual Report for the fiscal year ended December 31, 2017 on Form 10-K incorporated by reference in this joint proxy statement/prospectus.

The following summary estimated pro forma combined net proved developed and undeveloped oil, NGL and natural gas reserves should be read in
conjunction with the section entitled Unaudited Pro Forma

The following table sets forth summary pro forma information with respect to Encanas and Newfields combined oil, NGLs and natural
gas production for the year ended December 31, 2017 and nine months ended September 30, 2018. This pro forma information gives effect to the merger as if each had occurred on January 1, 2017. The Encana and Newfield production data
presented below was derived from the respective Annual Reports on Form 10-K for the year ended December 31, 2017, and the respective Quarterly Reports on
Form 10-Q for the quarterly period ended September 30, 2018.

Nine Months Ended September 30, 2018

EncanaHistoricalCanada

EncanaHistoricalU.S.

NewfieldHistoricalU.S.

Pro FormaCombinedU.S.

NewfieldHistoricalChina

Pro FormaCombinedTotal

Production:

Oil (MMbbls)

0.1

23.8

19.9

43.7

1.3

45.1

Natural Gas Liquids (MMbbls)

11.9

7.8

11.5

19.3



31.2

Natural Gas (Bcf)

266

41

117

158



424

Total (MMBOE)

56.4

38.4

50.9

89.3

1.3

147.0

Year Ended December 31, 2017

EncanaHistoricalCanada

EncanaHistoricalU.S.

NewfieldHistoricalU.S.

Pro FormaCombinedU.S.

NewfieldHistoricalChina

Pro FormaCombinedTotal

Oil (MMbbls)

0.1

27.7

22.3

50.0

1.7

51.8

Natural Gas Liquids (MMbbls)

10.6

8.7

11.6

20.3



30.9

Natural Gas (Bcf)

306

97

126

223



529

Total (MMBOE)

61.7

52.5

54.8

107.3

1.7

170.7

31

UNAUDITED COMPARATIVE PER SHARE DATA

The following tables present Encanas and Newfields historical and pro forma per share data for the year ended December 31,
2017 and for the nine months ended September 30, 2018. The pro forma per share data for the year ended December 31, 2017 and as of and for the nine months ended September 30, 2018 is presented as if the merger had been completed on
January 1, 2017. Except for the historical information for the year ended December 31, 2017, the information provided in the tables below is unaudited.

Historical per share data of Encana for the year ended December 31, 2017 and the nine months ended September 30, 2018 was derived
from Encanas historical financial statements for the respective periods. Historical per share data of Newfield for the year ended December 31, 2017 and the nine months ended September 30, 2018 was derived from Newfields
historical financial statements for the respective periods. This information should be read together with the historical consolidated financial statements and related notes of Encana and Newfield filed by each with the SEC, and that are incorporated
into this joint proxy statement/prospectus by reference. See Where You Can Find More Information beginning on page 196.

Unaudited pro forma combined per share data for the year ended December 31, 2017 and the nine months ended September 30, 2018 was
derived and should be read in conjunction with the unaudited pro forma condensed combined financial data included under Unaudited Pro Forma Condensed Combined Financial Statements beginning on page 156. The pro forma information is
presented for illustrative purposes only and is not necessarily indicative of the operating results or financial position that would have occurred if the merger had been completed as of the beginning of the period.

Nine Months Ended September 30, 2018

Encana Historical(unaudited)

Newfield Historical(unaudited)

Pro Forma Combined(unaudited)

Net Earnings (Loss) Per Share

Basic

$

0.04

$

2.15

$

0.28

Diluted

$

0.04

$

2.14

$

0.28

Book Value Per Share

$

6.82

$

9.25

$

6.86

Cash Dividends Per
Share(1)(3)

$

0.045



$

0.029

Year Ended December 31, 2017

Encana Historical(audited(4))

Newfield Historical(audited(4))

Pro Forma Combined(unaudited)

Net Earnings (Loss) Per Share

Basic

$

0.85

$

2.14

$

0.66

Diluted

$

0.85

$

2.13

$

0.66

Book Value Per Share

$

6.91

$

6.99



Cash Dividends Per
Share(2)(3)

$

0.06



$

0.038

(1)

On November 1, 2018, Encana announced the declaration of a dividend of $0.015 per share of outstanding
Encana common shares, payable on December 31, 2018 to Encana shareholders of record as of December 14, 2018. Encana also announced that following the close of the merger it intends to increase its future dividend by 25%. Future decisions
to pay dividends on Encana common shares will be at the discretion of the Encana board and will depend on the financial condition, results of operations, capital requirements, and other factors that the Encana board may deem relevant. See
Comparative Market Price and Dividend MattersDividends.

(2)

Newfield has not paid any cash dividends on its common stock and does not intend to do so in the foreseeable
future. See Dividends.

32

(3)

Subject to limited exceptions, including the payment of Encanas regular quarterly dividend of $0.015 per
Encana common share, the merger agreement prohibits Encana and Newfield (unless consented to in advance by the other, which consent may not be unreasonably withheld, conditioned or delayed) from paying dividends to their respective shareholders
until the earlier of the effective time of the merger and the termination of the merger agreement in accordance with its terms.

(4)

Other than Book Value per Share and Cash Dividends per Share.

33

COMPARATIVE MARKET PRICE AND DIVIDEND MATTERS

Encana common shares are listed on the NYSE and the TSX under the symbol ECA. Newfields common stock is listed on the NYSE
under the symbol NFX.

The following table sets forth, for the periods indicated, as reported by the NYSE and the TSX, the per
share high and low sales prices of Encana common shares and cash dividends declared for the same periods.

NYSE

TSX

CashDividend

High

Low

High

Low

2016

First Calendar Quarter

$

6.37

$

3.01

C$

8.26

C$

4.14

$

0.015

Second Calendar Quarter

$

9.03

$

5.63

C$

11.47

C$

7.41

$

0.015

Third Calendar Quarter

$

10.75

$

7.35

C$

13.87

C$

9.56

$

0.015

Fourth Calendar Quarter

$

13.40

$

8.96

C$

17.70

C$

12.03

$

0.015

2017

First Calendar Quarter

$

13.84

$

10.07

C$

18.13

C$

13.61

$

0.015

Second Calendar Quarter

$

12.25

$

8.02

C$

16.40

C$

10.64

$

0.015

Third Calendar Quarter

$

12.01

$

8.17

C$

14.97

C$

10.54

$

0.015

Fourth Calendar Quarter

$

13.52

$

10.16

C$

16.93

C$

13.03

$

0.015

2018

First Calendar Quarter

$

14.31

$

9.80

C$

17.94

C$

12.37

$

0.015

Second Calendar Quarter

$

13.94

$

10.28

C$

18.06

C$

13.20

$

0.015

Third Calendar Quarter

$

14.27

$

11.87

C$

18.54

C$

15.46

$

0.015

Fourth Calendar Quarter

$

13.60

$

5.00

C$

17.41

C$

6.90

$

0.015

2019

First Calendar Quarter (through January 7, 2019)

$

6.47

$

5.53

C$

8.61

C$

7.54



The following table sets forth, for the periods indicated, as reported by the NYSE, the per share high and low
sales prices of Newfield common stock and cash dividends declared for the same periods.

NYSE

CashDividend

High

Low

2016

First Calendar Quarter

$

34.97

$

20.84



Second Calendar Quarter

$

44.79

$

30.88



Third Calendar Quarter

$

47.56

$

39.25



Fourth Calendar Quarter

$

50.00

$

37.17



2017

First Calendar Quarter

$

43.74

$

33.00



Second Calendar Quarter

$

37.61

$

27.22



Third Calendar Quarter

$

30.05

$

24.41



Fourth Calendar Quarter

$

33.33

$

27.77



2018

First Calendar Quarter

$

35.20

$

22.72



Second Calendar Quarter

$

31.35

$

23.02



Third Calendar Quarter

$

31.46

$

25.26



Fourth Calendar Quarter

$

29.62

$

12.45



2019

First Calendar Quarter (through January 7, 2019)

$

16.59

$

14.02



34

As of the record date, there were 952,507,693 Encana common shares outstanding, and
200,933,274 shares of Newfield common stock outstanding.

Because the exchange ratio will not be adjusted for changes in the market price
of either Encana common shares or Newfield common stock, the market value of Encana common shares that Newfield stockholders will have the right to receive on the date the merger is completed may vary significantly from the market value of the
Encana common shares that Newfield stockholders would receive if the merger were completed on the date of this joint proxy statement/prospectus. As a result, you should obtain recent market prices of Encana common shares and Newfield common stock
prior to voting your shares. See Risk FactorsRisks Relating to the Merger.

The following table sets forth the closing
sale price per Encana common share and share of Newfield common stock as reported on the NYSE on October 31, 2018, the last trading day before the public announcement of the parties entering into the merger agreement, and on January 7,
2019 the last practicable trading day prior to the date of this joint proxy statement/prospectus. The table also shows the estimated implied value of the merger consideration proposed for each share of Newfield common stock as of the same two dates.
The implied value was calculated by multiplying the NYSE closing price of an Encana common share on the relevant date by the exchange ratio of 2.6719 Encana common shares for each share of Newfield common stock.

Encana commonshares (NYSE)

Newfieldcommon stock(NYSE)

Implied PerShare Value ofMergerConsideration

October 31, 2018

$

10.24

$

20.20

$

27.36

January 7, 2019

$

6.28

$

16.12

$

16.78

Encana shareholders and Newfield stockholders are encouraged to obtain current market quotations for Encana
common shares and Newfield common stock and to review carefully the other information contained in this joint proxy statement/prospectus or incorporated by reference herein. No assurance can be given concerning the market price of Encana common
shares before or after the effective date of the merger. See Where You Can Find More Information for the location of information incorporated by reference into this joint proxy statement/prospectus.

Dividends

Encana pays quarterly dividends to shareholders at the discretion of the Encana board. On November 1, 2018, Encana announced the
declaration of a dividend of $0.015 per share of outstanding Encana common shares, payable on December 31, 2018 to Encana shareholders of record as of December 14, 2018. Encana also announced that following the close of the merger it
intends to increase its regular dividend by 25%. Future decisions to pay dividends on Encana common shares will be at the discretion of the Encana board and will depend on the financial condition, results of operations, capital requirements, and
other factors that the Encana board may deem relevant.

Newfield has not paid any cash dividends on its common stock and does not intend
to do so in the foreseeable future. Newfield intends to retain earnings for the future operation and development of its business. Any future cash dividends to Newfield stockholders would depend on future earnings, capital requirements, its financial
condition and other factors determined by the Newfield board. Covenants contained in Newfields credit facility and the indentures governing Newfields debt securities could restrict the payment of dividends on Newfield common stock.

35

CAUTIONARY NOTE REGARDING OIL AND GAS RESERVE ESTIMATES

All reserves information presented herein was prepared in accordance with applicable SEC regulations. The SEC regulations applicable
to reserve reporting differ from the evaluation and reporting requirements prescribed by applicable Canadian securities laws under National Instrument 51-101Standards of Disclosure for Oil and Gas
Activities (NI 51-101) and the forms related thereto. Differences in the estimates of the reserve volumes and values between SEC requirements and NI 51-101
methodology may be material. Accordingly, information contained in this joint proxy statement/prospectus and the documents incorporated by reference herein containing operating and oil and gas reserve data may not be comparable to similar
information disclosed in accordance with NI 51-101.

CAUTIONARY
STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

Information both included and incorporated by reference in this joint proxy
statement/prospectus may contain certain forward-looking statements or information (collectively, forward-looking statements) within the meaning of Section 27A of the Securities Act, Section 21E of the Exchange Act, and the
United States Private Securities Litigation Reform Act of 1995, as amended. All statements, other than statements of historical fact, included in this joint proxy statement/prospectus that address activities, events or developments that Encana or
Newfield expects, believes or anticipates will or may occur in the future are forward-looking statements. Words such as estimate, project, predict, believe, expect, anticipate,
potential, create, intend, could, may, foresee, plan, will, guidance, look, outlook, future,
assume, forecast, focus, continue or the negative of such terms or other variations thereof and words and terms of similar substance used in connection with any discussion of future plans, actions, or
events identify forward-looking statements. Forward-looking statements also include statements relating to: the timing of closing of the merger; the expectation that the closing conditions to the merger, including Encana shareholder and Newfield
stockholder approvals and regulatory approvals, will be satisfied; the anticipated benefits from the merger; anticipated production and commodity mix of Encana, Newfield and the combined company; the anticipated synergies of the merger; the
expectation that the transaction is accretive to all metrics in Encanas five year plan; composition of the core assets of Encana, Newfield and the combined company, including allocation of capital and focus of development plans; growth in
long-term shareholder value; vision of being a leading North American resource play company; statements with respect to strategic objectives of Encana, Newfield and the combined company, including capital allocation strategy, focus of investment,
growth of high margin liquids volumes, operating and capital efficiencies and ability to preserve balance sheet strength; ability to lower costs and improve efficiencies to achieve competitive advantage; ability to repeat and deploy successful
practices across the combined companys multi-basin portfolio; balancing the combined companys commodity portfolio; anticipated commodity prices; success of and benefits from technology and innovation, including cube development approach
and advanced completion designs; ability to optimize well and completion designs; future well inventory; anticipated drilling, number of drilling rigs and the success thereof; anticipated drilling costs and cycle times; anticipated proceeds and
future benefits from various joint venture, partnership and other agreements; expected timing for construction of facilities and costs thereof; expansion of future midstream services; estimates of reserves and resources; expected production and
product types; statements regarding anticipated cash flow, non-GAAP cash flow margin and leverage ratios; anticipated cash and cash equivalents; anticipated hedging and outcomes of risk management program,
including exposure to certain commodity prices and foreign exchange, amount of hedged production, market access and physical sales locations; impact of changes in laws and regulations; compliance with environmental legislation and claims related to
the purported causes and impact of climate change, and the costs therefrom; adequacy of provisions for abandonment and site reclamation costs; financial flexibility and discipline; ability to meet financial obligations, manage debt and financial
ratios, finance growth and compliance with financial covenants; impact to the combined company as a result of changes to its credit rating; access to the credit facilities of Encana, Newfield and the combined company; planned annualized dividend and
the declaration and payment of future dividends, if any; Encanas normal course issuer bid program, including amounts and number of shares to be acquired, anticipated timeframe, method and location of purchases, and source of funding thereof;
adequacy of provision for taxes and legal claims of Encana, Newfield

36

and the combined company; projections and expectation of meeting the targets contained in Encanas and Newfields corporate guidance and Encanas five-year plan; ability to manage
cost inflation and expected cost structures, including expected operating, transportation and processing and administrative expenses; competitiveness and pace of growth of the assets of Encana, Newfield and the combined company within North America
and against its and their peers; outlook of oil and gas industry generally and impact of geopolitical environment; expected future interest expense; the commitments and obligations of Encana, Newfield and the combined company and anticipated
payments thereunder; statements with respect to future ceiling test impairments; and the possible impact and timing of accounting pronouncements, rule changes and standards; and the timing of the closing of the sale of Encanas San Juan assets
and the expectation that closing conditions and regulatory approvals in respect thereof will be satisfied.

Readers are cautioned against
unduly relying on forward-looking statements which, by their nature, involve numerous assumptions, risks and uncertainties that may cause such statements not to occur, or results to differ materially from those expressed or implied. These
assumptions include: expectations regarding the proposed merger; future commodity prices and differentials; foreign exchange rates; ability to access credit facilities and shelf prospectuses; assumptions contained in Encanas corporate
guidance, five-year plan and as specified herein; data contained in key modeling statistics; availability of attractive hedges and enforceability of risk management program; effectiveness of the drive to productivity and efficiencies of Encana,
Newfield and the combined company; results from innovations; expectation that counterparties will fulfill their obligations under the gathering, midstream and marketing agreements of Encana, Newfield and the combined company; access to
transportation and processing facilities where Encana and Newfield operate and where the combined company will operate; assumed tax, royalty and regulatory regimes; and expectations and projections made in light of, and generally consistent with,
the historical experience and perception of historical trends of Encana and Newfield, including with respect to the pace of technological development, benefits achieved and general industry expectations. Risks and uncertainties that may affect these
outcomes include: uncertainties relating to the Encanas ability to successfully integrate Newfields business and technologies; Encanas ability to realize the anticipated benefits of the merger, including the possibility that the
expected benefits from the merger will not be realized or will not be realized within the expected time period; the ability to obtain required Encana shareholder and Newfield stockholder approvals and regulatory approvals for the merger; timing of
such approvals and risk that regulatory approvals may result in the imposition of conditions that could adversely affect the expected benefits of the merger; the risk that the conditions to the merger are not satisfied on a timely basis or at all
and/or the failure of the merger to close for any other reason; the risks relating to the value of the Encana common shares to be issued in connection with the merger; the disruption to Encanas and Newfields respective businesses that
could result from the announcement of the merger; Encanas ability to implement Encanas plans, forecasts and other expectations with respect to Newfields business after the completion of the merger and to realize expected synergies;
disruption from the merger making it more difficult to maintain business and operational relationships; the amount of the costs, fees, expenses and charges related to the merger; unknown liabilities; the risk of litigation or regulatory actions
related to the merger; the occurrence of any event, change or other circumstances that could give rise to the termination of the merger agreement; the ability of Encana, Newfield and the combined company to successfully integrate acquired businesses
and technologies; ability to generate sufficient cash flow to meet obligations; commodity and commodity futures price volatility; sustained declines in commodity prices resulting in impairment of assets; actions of the Organization of the Petroleum
Exporting Countries (OPEC), its members and other state-controlled oil companies relating to oil price and production controls; ability to secure adequate transportation and potential pipeline curtailments; variability and discretion of the Encana
board and the Newfield board to declare and pay dividends, if any; timing and costs of well, facilities and pipeline construction; land, legal, regulatory and ownership complexities inherent in Canada, the U.S. and China; business interruption,
property and casualty losses or unexpected technical difficulties, including impact of weather; counterparty and credit risk; impact of a downgrade in a credit rating, and its impact on access to sources of liquidity; fluctuations in currency and
interest rates; risks associated with inflation rates; risks inherent in the corporate guidance of Encana, Newfield and the combined company; failure to achieve cost and efficiency initiatives; risks inherent in marketing operations; risks
associated with drilling; risks associated with technology, including electronic, cyber or physical security breaches; changes in or interpretation of royalty,

37

tax, environmental, greenhouse gas, carbon, accounting and other laws or regulations, including potential environmental liabilities that are not covered by an effective indemnity or insurance;
risks associated with existing and potential lawsuits and regulatory actions made against Encana, Newfield, the combined company or the merger; impact of disputes arising with its partners, including suspension of certain obligations and inability
to dispose of assets or interests in certain arrangements; the ability of Encana, Newfield and the combined company to acquire or find additional reserves; imprecision of reserves estimates and estimates of recoverable quantities, including future
net revenue estimates; risks associated with past and future acquisitions or divestitures of certain assets or other transactions or receipt of amounts contemplated under the merger agreements (such transactions may include third-party capital
investments, farm-outs or partnerships, which Encana or Newfield may refer to from time to time as partnerships or joint ventures and the funds received in respect thereof which Encana or Newfield may refer to from time to
time as proceeds, deferred purchase price and/or carry capital, regardless of the legal form) as a result of various conditions not being met; and other risks described in this joint proxy statement/prospectus
under the heading Risk Factors, in Item 1A Risk Factors of Encanas Annual Report for the fiscal year ended December 31, 2017 on Form 10-K incorporated by reference in this joint proxy
statement/prospectus, Item 1A Risk Factors of Encanas Quarterly Report for the quarterly period ended September 30, 2018 on Form 10-Q incorporated by reference in this joint proxy
statement/prospectus, risks and uncertainties impacting Encanas business as described from time to time in Encanas other periodic filings as filed on SEDAR and EDGAR, Item 1A Risk Factors of Newfields Annual Report for the fiscal
year ended December 31, 2017 on Form 10-K incorporated by reference in this joint proxy statement/prospectus and risks and uncertainties impacting Newfields business as described from time to time
in Newfields other periodic filings as filed on EDGAR.

Although Encana and Newfield believe the expectations represented by such
forward-looking statements are reasonable, there can be no assurance that such expectations will prove to be correct. Readers are cautioned that the assumptions, risks and uncertainties referenced above and in the documents incorporated by reference
herein are not exhaustive. Forward-looking statements are made as of the date of this joint proxy statement/prospectus (or, in the case of a document incorporated by reference, the date of such document incorporated by reference) and, except as
required by law, neither Encana nor Newfield undertakes any obligation to update publicly or revise any forward-looking statements whether as a result of changes in internal estimates or expectations, new information, subsequent events or
circumstances or otherwise. The forward-looking statements contained or incorporated by reference in this joint proxy statement/prospectus are expressly qualified by these cautionary statements.

The reader should read carefully the risk factors described in this joint proxy statement/prospectus and in the documents incorporated by
reference in document for a description of certain risks that could, among other things, cause actual results to differ from these forward-looking statements.

38

RISK FACTORS

In addition to the other information included and incorporated by reference into this joint proxy statement/prospectus, including the
matters addressed in the section entitled Cautionary Statement Regarding Forward-Looking Statements, you should carefully consider the following risk factors before deciding whether to vote for the merger agreement proposal, in the case
of Newfield stockholders, or for the share issuance proposal, in the case of Encana shareholders. In addition, you should read and consider the risks associated with each of the businesses of Newfield and Encana because these risks will relate to
the combined company following the completion of the merger. Descriptions of some of these risks can be found in the Annual Reports of Encana and Newfield on Form 10-K for the fiscal year ended
December 31, 2017, and any amendments thereto for each of Encana and Newfield, as such risks may be updated or supplemented in each companys subsequently filed Quarterly Reports on Form 10-Q or
Current Reports on Form 8-K, which are incorporated by reference into this joint proxy statement/prospectus. You should also consider the other information in this joint proxy statement/prospectus and the
other documents incorporated by reference into this joint proxy statement/prospectus. See the section entitled Where You Can Find More Information.

Risks Relating to the Merger

Because the exchange ratio is fixed and the market prices of Encana common shares and Newfield common stock may fluctuate, Newfield stockholders cannot
be sure of the value of the Encana common shares they will receive on the closing date.

At the effective time, each share of
Newfield common stock (other than excluded shares) will be cancelled and converted into the right to receive 2.6719 Encana common shares with cash paid in lieu of the issuance of fractional Encana common shares, if any. If applicable, the exchange
ratio will be adjusted appropriately to fully reflect the effect of any stock dividend, subdivision, stock split, reclassification, reorganization or other similar change with respect to the shares of either Encana common shares or Newfield common
stock prior to the completion of the merger. The exchange ratio will not, however, be adjusted for changes in the market price of either Encana common shares or Newfield common stock between the date of signing the merger agreement and the effective
time. Accordingly, at the time of the Encana special meeting and at the time of the Newfield special meeting, neither Encana shareholders nor Newfield stockholders will know, or be able to determine, the value of Encana common shares to be issued in
connection with the merger. For that reason, the market price of Encana common shares on the date of the Encana special meeting and the Newfield special meeting may not be indicative of the value of Encana common shares that Newfield stockholders
will receive upon completion of the merger.

The market prices of Encana common shares and Newfield common stock are subject to general
price fluctuations in the market for publicly traded equity securities and have experienced volatility in the past. Neither Encana nor Newfield is permitted to terminate the merger agreement or re-solicit the
vote of Encana shareholders or Newfield stockholders, as applicable, solely because of changes in the market prices of either Newfields common stock or Encanas common shares. Share price changes may result from a variety of factors,
including general market and economic conditions and changes in the respective businesses, operations and prospects, and regulatory considerations of Encana and Newfield. Market assessments of the benefits of the proposed merger and the likelihood
that the transactions will be completed, as well as general and industry-specific market and economic conditions, may also affect market prices of Encana common shares and Newfield common stock. Many of these factors are beyond Encanas and
Newfields control. Newfield stockholders should obtain current market quotations for Encana common shares and for shares of Newfield common stock.

The market value of Encana common shares could be negatively affected by risks and conditions that apply to Encana, which may be different from the
risks and conditions applicable to Newfield, and Encana shareholders will have different rights than Newfield stockholders.

Following the merger, Encana shareholders and former Newfield stockholders will own interests in a combined company operating an expanded
business with more assets and a different mix of liabilities, in various

39

jurisdictions in which Encana does not currently operate. The business of Encana and its subsidiaries and other companies it may acquire in the future are different from those of Newfield. There
is a risk that various factors, conditions and developments that would not affect the price of Newfield common stock could negatively affect the price of Encana common shares. Current Encana shareholders and Newfield stockholders may not wish to
continue to invest in the combined company, or may wish to reduce their investment in the combined company, including in order to comply with institutional investing guidelines, to increase diversification, to track any rebalancing of stock indices
in which Encana common shares are included or not included, to respond to the risk profile of the combined company or to realize a gain. In addition, if, following the merger, large amounts of Encana common shares are sold, the price of Encana
common shares could decline.

Encana shareholders will have rights that differ from the rights they had as Newfield stockholders before
the merger. For a detailed comparison of the rights of Encana shareholders to the rights of Newfield stockholders, see Comparison of Rights of Encana Shareholders and Newfield Stockholders.

The merger is subject to conditions, including certain conditions that may not be satisfied, or completed on a timely basis, if at all. Failure to
complete the merger could have material and adverse effects on Encana and Newfield.

Completion of the merger is subject to a
number of conditions, including, among other things, (i) the receipt of certain approvals of Encana shareholders and Newfield stockholders, (ii) the expiration or termination of the waiting period under the Hart-Scott-Rodino Antitrust
Improvements Act of 1976, as amended, (iii) the effectiveness of the registration statement on Form S-4 that Encana is obligated to file with the SEC in connection with the issuance of Encana common
shares in the merger, (iv) the authorization for listing of the Encana common shares to be issued in the merger on the NYSE and the TSX, (v) the accuracy of each partys representations and warranties (subject to certain materiality
qualifiers) and compliance by each party with its covenants under the merger agreement in all material respects and (vi) the absence of legal restraints prohibiting or restraining the merger. Such conditions make the completion and timing of
the completion of the merger uncertain. Also, either Encana or Newfield may terminate the merger agreement if the merger has not been consummated by the outside date, except that this right to terminate the merger agreement will not be available to
any party whose material breach of any provision of the merger agreement resulted in the failure of the merger to be consummated on or before that date. See the section entitled The Merger AgreementConditions to Completion of the
Merger for a more detailed discussion.

If the merger is not completed, Encanas and Newfields respective ongoing
businesses may be adversely affected and, without realizing any of the benefits of having completed the merger, Encana and Newfield will be subject to a number of risks, including the following:



Encana and Newfield will be required to pay their respective costs relating to the merger, such as legal,
accounting, financial advisory and printing fees, whether or not the merger is completed;



time and resources committed by Encanas and Newfields management to matters relating to the merger
could otherwise have been devoted to pursuing other beneficial opportunities;



the market price of Encana common shares or Newfield common stock could be impacted to the extent that the
current market price reflects a market assumption that the merger will be completed;



if the merger agreement is terminated and the Newfield board seeks another business combination, Newfield
stockholders cannot be certain that Newfield will be able to find a party willing to enter into a transaction agreement on terms equivalent to or more attractive than the terms agreed to in the merger agreement; and



if the merger agreement is terminated and the Encana board seeks another acquisition, Encana shareholders cannot
be certain that Encana will be able to find a party willing to enter into a transaction as attractive to Encana as the acquisition of Newfield.

40

The merger agreement contains provisions that limit Newfields and Encanas ability to
pursue alternatives to the merger, could discourage a potential competing acquiror of Encana or Newfield from making a favorable alternative transaction proposal and, in specified circumstances, Newfield may be required to pay Encana a termination
fee of $150 million, or Encana may be required to pay Newfield a termination fee of $300 million.

The merger agreement
contains certain provisions that restrict Newfields and Encanas ability to solicit, initiate or knowingly encourage or facilitate, among other things, any inquiries, proposals, offers, or requests for information regarding, or the making
of a competing proposal, engage in any discussions or negotiations with respect to a competing proposal or furnish any non-public information to any person in connection with a competing proposal. Further,
even if the Newfield board or the Encana board changes its recommendation with respect to the merger agreement proposal or the share issuance proposal, as applicable, unless the merger agreement has been terminated in accordance with its terms, both
parties will still be required to submit the merger agreement proposal and the share issuance proposal, as applicable, to a vote at its special meeting. In addition, the other party generally has an opportunity to offer to modify the terms of the
merger in response to any third-party alternative transaction proposal before a partys board of directors may change its recommendation with respect to the merger agreement proposal or the share issuance proposal, as applicable. In some
circumstances, upon termination of the merger agreement, Newfield may be required to pay Encana a termination fee of $150 million, or Encana may be required to pay Newfield a termination fee of $300 million. In other circumstances, upon
termination of the merger agreement, either Encana or Newfield could be required to pay the other party $50 million for costs, fees and expenses incurred by such other party. See the sections entitled The Merger AgreementNo
Solicitation of Alternative Proposals, The Merger AgreementTermination of the Merger Agreement and The Merger AgreementExpenses and Termination Fees Relating to the Termination of the Merger Agreement.

These provisions could discourage a potential third-party acquirer or merger partner that might have an interest in acquiring all or a
significant portion of Newfield or Encana in pursuing an alternative transaction with either from considering or proposing such a transaction, even if, in the case of an acquisition of Newfield, it were prepared to pay consideration with a higher
per share price than the per share price proposed to be received in the merger or might result in a potential third-party acquiror or merger partner proposing to pay a lower price to the stockholders of Newfield or the shareholders of Encana than it
might otherwise have proposed to pay because of the added expense of the termination fee that may become payable in certain circumstances.

Newfields executive officers and directors have interests in the merger that may be different from, or in addition to, the interests of Newfield
stockholders generally.

When considering the recommendation of the Newfield board with respect to the merger, you should be aware
that Newfields executive officers and directors may have interests in the merger that are different from, or in addition to, those of Newfield stockholders more generally. The Newfield board was aware of these interests during its
deliberations on the merits of the merger and in deciding to recommend that Newfield stockholders vote for the approval of the merger agreement proposal at the Newfield special meeting.

These interests include, among others, the treatment of outstanding time-based restricted stock units and performance-based restricted stock
units. Upon completion of the merger, each outstanding restricted stock award, time-based restricted stock unit award, performance-based restricted stock unit award and share of notional stock in respect of Newfield common stock will be treated as
described in The MergerTreatment of Newfield Equity Awards in the Merger beginning on page 134.

See the section of
this joint proxy statement/prospectus entitled The MergerInterests of Certain Newfield Directors and Executive Officers in the Merger for a more detailed description of the interests of Newfields executive officers and
directors.

41

Newfield and Encana will be subject to business uncertainties while the merger is pending, which could
adversely affect their businesses.

In connection with the pendency of the merger, it is possible that certain persons with whom
Newfield and Encana have a business relationship may delay or defer certain business decisions or might decide to seek to terminate, change or renegotiate their relationships with Newfield or Encana, as the case may be, as a result of the merger,
which could negatively affect Newfields or Encanas revenues, earnings and cash flows, as well as the market price of Newfields common stock or Encanas common shares, regardless of whether the merger is completed.

Under the terms of the merger agreement, each of Newfield and Encana are subject to certain restrictions on the conduct of its business prior
to the completion of the merger, which may adversely affect its ability to execute certain of its business strategies, including the ability in certain cases to enter into certain contracts, acquire or dispose of certain assets, or incur certain
indebtedness or incur certain capital expenditures, as applicable. Such limitations could negatively affect Newfields and Encanas businesses and operations prior to the completion of the merger.

The merger is subject to the receipt of approvals, consents or clearances from regulatory authorities that may impose conditions that could have an
adverse effect on Encana or Newfield or, if not obtained, could prevent completion of the merger.

Completion of the merger is
conditioned upon the receipt of certain governmental approvals. Although each party has agreed to use their respective best efforts to obtain the requisite governmental approvals, there can be no assurance that these approvals will be obtained and
that the other conditions to completing the merger will be satisfied. In addition, the governmental authorities from which the regulatory approvals are required may impose conditions on the completion of the merger or require changes to the terms of
the merger or other agreements to be entered into in connection with the merger agreement. Such conditions or changes and the process of obtaining regulatory approvals could have the effect of delaying or impeding consummation of the transaction or
of imposing additional costs or limitations on Encana or Newfield following completion of the merger, any of which might have an adverse effect on Encana or Newfield following completion of the merger. For additional information about the regulatory
approvals process, see The MergerRegulatory Approvals Required to Complete the Merger.

The unaudited pro forma condensed combined
financial statements in this joint proxy statement/prospectus are presented for illustrative purposes only and may not be reflective of the operating results and financial condition of Encana following the occurrence of the pro forma events.

The unaudited pro forma condensed combined financial statements in this joint proxy statement/prospectus are presented for
illustrative purposes only, has been prepared based on available information and certain assumptions and estimates that Encana and Newfield believe are reasonable and is not necessarily indicative of what Encanas actual financial position or
results of operations would have been had the pro forma events been completed on the dates indicated. Further, Encanas actual results and financial position after the pro forma events occur may differ materially and adversely from the
unaudited pro forma condensed combined financial statements that are included in this joint proxy statement/prospectus. The unaudited pro forma condensed combined financial statements have been prepared with the assumption that Encana will be
identified as the acquirer under GAAP and reflects adjustments based upon preliminary estimates of the fair value of assets to be acquired and liabilities to be assumed.

Current Encana shareholders and current Newfield stockholders will have a reduced ownership interest in the combined company.

In connection with the completion of the merger and the transactions contemplated by the merger agreement, based on the number of issued and
outstanding shares of Newfield common stock as of October 29,

42

2018 and the number of outstanding Newfield equity awards currently estimated to be payable in Encana common shares in connection with the merger, Encana anticipates issuing up to approximately
547.5 million common shares. The actual number of Encana common shares to be issued in the merger will be determined at the completion of the merger based on the number of shares of Newfield common stock outstanding at the time of the
consummation of the merger. The issuance of these new shares could have the effect of depressing the market price of Encanas common shares, through dilution of earnings per share or otherwise. Any dilution of, or delay of any accretion to,
Encanas earnings per share could cause the price of its common shares to decline or increase at a reduced rate.

Immediately after
the merger is completed, it is expected that current Encana shareholders will own approximately 63.5% and current Newfield stockholders will own approximately 36.5% of the combined companys common shares outstanding, respectively. As a result,
current Encana shareholders and current Newfield stockholders will own a smaller percentage of the combined company than they currently own of Encana and Newfield, respectively, and will have less influence on the policies of the combined company
than they currently have on the policies of Encana and Newfield, respectively.

Completion of the merger may trigger change in control or other
provisions in certain agreements to which Newfield is a party.

The completion of the merger may trigger change in control or other
provisions in certain agreements to which Newfield is a party. If Encana and Newfield are unable to negotiate waivers of those provisions, the counterparties may exercise their rights and remedies under the agreements, potentially terminating the
agreements or seeking monetary damages or, in certain situations, Encana may be required to make an offer to purchase outstanding debt securities of Newfield. Even if Encana and Newfield are able to negotiate waivers, the counterparties may require
a fee for such waivers or seek to renegotiate the agreements on terms less favorable to Newfield.

Risks Relating to Encana
after Completion of the Merger

Following the merger, the market price of Encana common shares may be volatile, and Encana shareholders could
lose a significant portion of their investment due to drops in the market price of Encana common shares following completion of the merger.

The market price of Encana common shares may be volatile, and following completion of the merger, shareholders may not be able to resell Encana
common shares at or above the price at which they acquired such shares pursuant to the merger agreement or otherwise due to fluctuations in its market price, including changes in price caused by factors unrelated to Encanas performance or
prospects.

Specific factors that may have a significant effect on the market price for Encana common shares include, among others, the
following:

adverse conditions in the financial markets or general U.S. or international economic conditions, including those
resulting from war, incidents of terrorism and responses to such events; and



sales of Encana common shares by significant shareholders.

If the merger is completed, Encana may not achieve the intended benefits and the merger may disrupt its current plans or operations.

There can be no assurance that Encana will be able to successfully integrate Newfields assets or otherwise realize the expected benefits
of the merger. Difficulties in integrating Newfield into Encana may result in the combined company performing differently than expected, in operational challenges or in the failure to realize anticipated synergies and efficiencies. Potential
difficulties that may be encountered in the integration process include, among other factors: the inability to successfully integrate the businesses of Newfield into Encana in a manner that permits Encana to achieve the full revenue and cost savings
anticipated from the merger; complexities associated with managing a larger, more complex, integrated business; not realizing anticipated operating synergies; integrating personnel from the two companies and the loss of key employees; potential
unknown liabilities and unforeseen expenses, delays or regulatory conditions associated with and following completion of the merger; integrating relationships with vendors and business partners; performance shortfalls at one or both of the companies
as a result of the diversion of managements attention caused by completing the merger and planning to integrate Newfields operations into Encana; and the disruption of, or the loss of momentum in, each companys ongoing business or
inconsistencies between the companies standards, controls, procedures and policies.

Encanas outstanding debt is periodically rated by nationally
recognized credit rating agencies. The credit ratings are based upon Encanas operating performance, liquidity and leverage ratios, overall financial position, and other factors viewed by the credit rating agencies as relevant to both
Encanas industry and the economic outlook. Encanas credit rating may affect the amount of capital Encana can access, as well as the terms of any financing Encana obtains. Because Encana relies in part on debt financing to fund growth,
adverse changes in Encanas credit rating may have a negative effect on Encanas future growth.

After the merger is completed, Newfield
stockholders will become shareholders of a Canadian corporation and have their rights as shareholders governed by Encanas organizational documents and Canadian law.

Upon consummation of the merger, Newfield stockholders will receive Encana common shares that will be governed by Encanas organizational
documents and the CBCA. For a detailed discussion of the differences between rights as an Encana shareholder and rights as a Newfield stockholder, see Comparison of Rights of Encana Shareholders and Newfield Stockholders.

Encana and Newfield are expected to incur significant transaction and acquisition-related costs in connection with the merger.

Encana and Newfield have incurred and are expected to continue to incur a number of non-recurring costs
associated with negotiating and completing the merger, combining the operations of the two companies and achieving desired synergies. These costs may be substantial and, in many cases, will be borne by Encana and Newfield whether or not the merger
is completed. A substantial majority of non-recurring expenses will consist of transaction costs and include, among others, fees paid to financial, legal and other advisors, employee retention, severance and
benefit costs and filing fees. Encana will also incur costs related to formulating and implementing integration plans, including facilities and systems consolidation costs and other employment-related costs. Encana and Newfield continue to assess
the magnitude of these costs, and additional unanticipated

44

costs may be incurred in connection with the integration of the two companies businesses. The elimination of duplicative costs, as well as the realization of other efficiencies related to
the integration of the businesses, may not initially offset integration-related costs or achieve a net benefit in the near term, or at all. Any unanticipated costs and expenses could have an adverse effect on Encanas financial condition and
operating results following the completion of the merger.

While Encana and Newfield have assumed that a certain level of expenses would
be incurred, there are many factors beyond their control that could affect the total amount or the timing of the expenses.

Other Risk Factors of Encana and Newfield

Encanas and Newfields businesses are and will be subject to the risks described above. In addition, Encana and Newfield are, and
will continue to be subject to the risks described in Encanas and Newfields Annual Reports on Form 10-K for the fiscal year ended December 31, 2017, as updated by subsequent Quarterly
Reports on Form 10-Q and Current Reports on Form 8-K, all of which are filed with the SEC and incorporated by reference into this joint proxy
statement/prospectus. The risks described above and in those filings represent all known material risks with respect to Encanas and Newfields businesses. See Where You Can Find More Information for the location of information
incorporated by reference into this joint proxy statement/prospectus.

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INFORMATION ABOUT ENCANA

Encana Corporation

Encana is a leading North American energy producer that is focused on developing its multi-basin portfolio of oil, NGL and natural gas
producing plays. Encanas operations also include the marketing of oil, NGLs and natural gas. All of Encanas reserves and production are located in North America.

Encanas common shares are listed and posted for trading on the NYSE and the TSX under the symbol ECA. Encana is incorporated
under the CBCA and was formed in 2002 through the business combination of two predecessor companies.

The principal executive offices of
Encana are located at Suite 4400, 500 Centre Street S.E., Calgary, Alberta T2P 2S5, Canada and its telephone number is (403) 645-2000. Additional information about Encana and its subsidiaries is included in
documents incorporated by reference into this joint proxy statement/prospectus. See Where You Can Find More Information.

Neapolitan Merger Corp.

Neapolitan Merger Corp., a Delaware corporation (referred to previously in this joint proxy
statement/prospectus as Merger Sub), is a wholly-owned indirect subsidiary of Encana. Merger Sub is newly formed, and was organized for the purpose of consummating the merger. Merger Sub has engaged in no business activities to date and it has no
material assets or liabilities of any kind, other than those incident to its formation and those incurred in connection with the merger. Merger Subs address is 370 17th Street, Suite 1700,
Denver, Colorado 80202.

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INFORMATION ABOUT NEWFIELD

Newfield is a Delaware corporation, incorporated in 1988 and publicly traded on the NYSE since 1993. Newfield has been a member of the S&P
500 Index since 2010. Newfields operations are onshore and focus primarily on large scale, liquids-rich resource plays in the Anadarko Basin of Oklahoma, the Williston Basin of North Dakota and the Uinta Basin of Utah. In addition, Newfield
has oil assets offshore of China and gas assets in the Arkoma Basin of Oklahoma. Shares of Newfield common stock are listed for trading on the NYSE under the symbol NFX.

The principal executive offices of Newfield are located at 4 Waterway Square Place, Suite 100, The Woodlands, Texas 77380 and its telephone
number is (281) 210-5100. Additional information about Newfield and its subsidiaries is included in documents incorporated by reference into this joint proxy statement/prospectus. See Where You Can
Find More Information.

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ENCANA SPECIAL MEETING

General

This
joint proxy statement/prospectus is being provided to Encana shareholders as part of a solicitation of proxies by the Encana board for use at the Encana special meeting and at any adjournments or postponements of such special meeting. This joint
proxy statement/prospectus provides Encana shareholders with important information about the Encana special meeting and should be read carefully in its entirety.

Date, Time and Place of the Encana Special Meeting

The Encana special meeting will be held on February 12, 2019 at the Oddfellows Building, Ballroom (Floor 4), 100  6th Avenue S.W.,
Calgary, Alberta, at 8:00 a.m., Mountain Time.

Purposes of the Encana Special Meeting

The Encana special meeting is being held to consider and vote on the following proposals:



Proposal 1: To approve the issuance of Encana common shares to Newfield stockholders
in connection with the merger (referred to previously in this joint proxy statement/prospectus as the share issuance proposal); and



Proposal 2: To approve the adjournment of the Encana special meeting, if necessary or
appropriate, to solicit additional proxies if there are not sufficient votes to approve the share issuance proposal (referred to previously in this joint proxy statement/prospectus as the Encana adjournment proposal).

The Encana board has (i) unanimously determined that the terms of the merger agreement and the transactions
contemplated thereby, including the merger and the share issuance, are in the best interests of Encana, (ii) unanimously approved the execution and delivery by Encana of the merger agreement, the performance by Encana of its covenants and
agreements contained therein and the consummation of the transactions contemplated by the merger agreement, including the merger and the share issuance, upon the terms and subject to the conditions therein, (iii) unanimously directed that the
merger agreement be submitted to the Encana shareholders at the Encana special meeting to approve the share issuance, and (iv) unanimously resolved to recommend that the Encana shareholders approve the share issuance.

This joint proxy statement/prospectus contains important information regarding these proposals and factors that Encana shareholders should
consider when deciding how to cast their votes. Encana shareholders are encouraged to read the entire document carefully, including the annexes to and documents incorporated by reference into this joint proxy statement/prospectus, for more detailed
information regarding the merger agreement, including the share issuance proposal.

Attendance at the Encana Special Meeting

Only Encana shareholders of record as of the close of business on the record date, beneficial owners of Encana common shares as of the
close of business on the record date, holders of valid proxies for the Encana special meeting and invited guests of Encana may attend the Encana special meeting. An Encana shareholder has the right to appoint a person or company (who does not
have to be an Encana shareholder or other

48

person designated in the proxy card or voting information form) to be their representative at the Encana special meeting. Such appointment may be exercised by inserting the name of
the appointed representative in the blank space provided for that purpose. If you cannot attend the Encana special meeting in person, you are requested to vote in accordance with the instructions in How to Vote below.

Seating is limited and will be offered on a first come, first served basis. Shareholders must present a form of governmental photo
identification, such as a drivers license, in order to be admitted to the Encana special meeting. No cameras, laptops, recording equipment or other similar electronic devices, signs, placards, briefcases, backpacks, large bags or packages will
be permitted in the Encana special meeting. Encana reserves the right to deny admittance to any Encana shareholder who attempts to bring any such item into the Encana special meeting. Small purses are permissible, but they and any bags or packages
permitted in the Encana special meeting room will be subject to inspection. The use of mobile phones or other communication devices, tablets and similar electronic devices during the Encana special meeting is prohibited, and such devices must be
turned off and put away before entering the meeting room. All security procedures and instructions require strict adherence. By attending the Encana special meeting, Encana shareholders agree to abide by the agenda and procedures for the Encana
special meeting, copies of which will be distributed to attendees at the Encana special meeting.

Record Date

The record date for the determination of Encana shareholders entitled to notice of and to vote at the Encana special meeting is January 8,
2019. Only Encana shareholders who held Encana common shares of record at the close of business on January 8, 2019 are entitled to vote at the Encana special meeting and any adjournment or postponement of the Encana special meeting, so long as such
shares remain outstanding on the date of the Encana special meeting.

Outstanding Shares as of Record Date

As of the record date, there were 952,507,693 Encana common shares outstanding, held by 24,193 holders of record. Each Encana common share
entitles its holder of record to one vote at the Encana special meeting. Encana common shares are the only class of shares entitled to vote at the Encana special meeting, and Encana shareholders are entitled to vote on each proposal presented.

A complete list of registered Encana shareholders entitled to vote at the Encana special meeting will be available for inspection at the place
of the Encana special meeting during the meeting.

Quorum

In order for business to be conducted at the Encana special meeting, a quorum must be present. A quorum at the Encana special meeting
requires the presence of at least two persons present in person, each being an Encana shareholder or duly appointed proxyholder of an Encana shareholder, together holding at least 25% of the total issued and outstanding Encana common shares entitled
to vote at the Encana special meeting. For purposes of determining whether there is a quorum, all shares that are present, including abstentions, will count towards the quorum.

Vote Required

The votes required for each proposal are as follows:

Proposal 1the share issuance proposal.The affirmative vote of a majority of votes cast by Encana
shareholders entitled to vote thereon and present in person or represented by proxy at the Encana special meeting is required to approve the share issuance proposal. Abstentions are considered Encana common shares present and entitled to vote and
will have the same effect as a vote against the share issuance proposal. The failure of

49

any Encana shareholder to submit a vote (e.g., by not submitting a proxy or not voting in person) will not be counted in determining the votes cast in connection with the share issuance
proposal. Because the share issuance proposal is non-routine, brokers, banks and other nominees do not have discretionary authority to vote on the share issuance proposal and will not be able to vote on the
share issuance proposal absent instructions from the beneficial owner. The failure of a beneficial owner to provide voting instructions to its broker, bank or other nominee will result in the applicable shares not being counted in determining the
votes cast in connection with the share issuance proposal, and will therefore have no effect on the outcome of the share issuance proposal.

Proposal 2the Encana adjournment proposal.The affirmative vote of a majority of votes cast by Encana
shareholders entitled to vote thereon and present in person or represented by proxy at the Encana special meeting is required to approve the Encana adjournment proposal. Abstentions will not be treated as votes cast and, as a result, any abstention
will have no effect on the outcome of the Encana adjournment proposal. The failure of any Encana shareholder to submit a vote (e.g., not submitting a proxy or not voting in person) will not be counted in determining the votes cast in
connection with the Encana adjournment proposal. Because the Encana adjournment proposal is non-routine, brokers, banks and other nominees do not have discretionary authority to vote on the Encana adjournment
proposal and will not be able to vote on the Encana adjournment proposal absent instructions from the beneficial owner. The failure of a beneficial owner to provide voting instructions to its broker, bank or other nominee will result in the
applicable shares not being counted in determining the votes cast in connection with the Encana adjournment proposal, and will therefore have no effect on the outcome of the Encana adjournment proposal.

If Encana common shares are held in the name of a broker, bank or other nominee, the beneficial owner of such shares will receive separate
instructions from his or her broker, bank or other nominee describing how to vote such shares.

A
so-called broker non-vote results when banks, brokers and other nominees return a valid proxy but do not vote on a particular proposal because they do not
have discretionary authority to vote on the matter and have not received specific voting instructions from the beneficial owner of such shares. Encana and Newfield do not expect any broker non-votes at the
Encana special meeting or Newfield special meeting because the rules applicable to banks, brokers and other nominees only provide brokers with discretionary authority to vote on proposals that are considered routine, whereas each of the proposals to
be presented at the Encana special meeting and Newfield special meeting are considered non-routine. As a result, no broker will be permitted to vote shares at the Encana special meeting or Newfield special
meeting without receiving instructions from the beneficial owner of such shares.

How to Vote

Encana shareholders of record as of the close of business on the record date may have their Encana common shares voted by submitting a proxy or
may vote in person at the Encana special meeting by following the instructions provided on the enclosed proxy card. Encana recommends that Encana shareholders entitled to vote submit a proxy prior to the Encana special meeting even if they plan to
attend the Encana special meeting.

Encana shareholders who hold their Encana common shares beneficially in street name and
wish to submit a proxy must provide instructions to the broker, bank, trustee or other nominee that holds their shares of record as to how to vote their shares with respect to Proposals 1 and 2. Encana shareholders who hold their Encana common
shares beneficially and wish to vote in person at the Encana special meeting must obtain proxies issued in their own names.

Encana
shareholders of record may submit a proxy in one of three ways or vote in person at the Encana special meeting:



Internet: Encana shareholders may submit their proxy over the Internet at the web address shown on
their proxy card. Internet voting is available 24 hours a day and will be accessible until 8:00 a.m.,

50

Mountain Time, on February 8, 2019. Shareholders will be given an opportunity to confirm that their voting instructions have been properly recorded. Encana shareholders who submit a proxy this
way need not send in their proxy card.



Telephone: Encana shareholders may submit their proxy by calling the toll-free telephone number
shown on their proxy card. Telephone voting is available 24 hours a day and will be accessible until 8:00 a.m., Mountain Time, on February 8, 2019. Easy-to-follow
voice prompts will guide shareholders through the voting and allow them to confirm that their instructions have been properly recorded. Encana shareholders who submit a proxy this way need not send in their proxy card.



Mail: Encana shareholders may submit their proxy by properly completing, signing, dating and
mailing their proxy card in the postage-paid envelope (if mailed in the United States or Canada) included with this joint proxy statement/prospectus. Encana shareholders who vote this way should mail the proxy card early enough so that it is
received by 8:00 a.m., Mountain Time, on February 8, 2019 before the date of the Encana special meeting.



In Person: Encana shareholders may vote in person at the Encana special meeting or by sending a
representative with an acceptable proxy that has been signed and dated; attendance at the Encana special meeting will not, however, in and of itself constitute a vote or a revocation of a prior proxy.

Encana may also use Broadridge Financial Solution Inc.s QuickVote service to assist beneficial shareholders with voting their
common shares. Beneficial shareholders may be contacted by MacKenzie Partners or Kingsdale Advisors to obtain a vote conveniently, quickly and directly over the telephone.

Encana shareholders are encouraged to submit a proxy promptly. Each valid proxy received in time will be voted at the Encana special meeting
according to the choice specified, if any. Executed but uninstructed proxies (i.e., proxies that are properly signed, dated and returned but are not marked to tell the proxies how to vote) will be voted in accordance with the recommendations
of the Encana board. The time limit for the deposit of proxies may be waived or extended by the chair of the meeting at his or her discretion without notice.

Encana shareholders who hold Encana common shares in an Encana employee benefit plan will receive a separate voting direction card. The
trustee and/or plan administrator of the applicable Encana employee benefit plan will vote such Encana common shares in accordance with the instructions on such returned direction cards.

For Encana shareholders who hold Encana common shares in an Encana employee benefit plan who do not timely return a direction card, the
trustee and/or plan administrator will vote the Encana common shares held by such Encana shareholder in accordance with their normal process. For Encana shareholders who hold Encana common shares in an Encana employee benefit plan who return a
direction card with no instructions, the trustee and/or plan administrator will vote the Encana common shares held by such Encana shareholder FOR the share issuance proposal and FOR the Encana adjournment proposal.

Please note that the direction cards have an earlier return date than the proxy cards. Encana shareholders who hold Encana common shares in an
Encana employee benefit plan should review their direction card for the date by which instructions must be received in order for such Encana common shares to be voted.

In the case of Internet or telephone voting, Encana shareholders who hold Encana common shares in an Encana employee benefit plans should have
their direction card in hand and retain the card until they have completed the voting process. Encana shareholders who hold Encana common shares in an Encana employee benefit plan who vote by Internet or telephone do not need to return the direction
card by mail.

Please note that no votes will be accepted at the Encana special meeting in respect of Encana common shares held in an
Encana employee benefit plan and that all such votes must be voted prior to the Encana special meeting.

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Proxies and Revocation

Encana shareholders of record may revoke their proxies at any time before their Encana common shares are voted at the Encana special meeting in
any of the following ways:



sending a written notice of revocation to Encana at Suite 4400, 500 Centre Street S.E., P.O. Box 2850, Calgary,
Alberta T2P2S5, Attention: Corporate Secretary, which must be received before their shares are voted at the Encana special meeting;



properly submitting a new, later-dated proxy card, which must be received by 8:00 a.m., Mountain Time, on
February 8, 2019 (in which case only the later-dated proxy is counted and the earlier proxy is revoked);



submitting a proxy via the Internet or by telephone at a later date, which must be received by 8:00 a.m.,
Mountain Time, on February 8, 2019 (in which case only the later-dated proxy is counted and the earlier proxy is revoked); or



attending the Encana special meeting and voting in person; attendance at the Encana special meeting will not,
however, in and of itself, constitute a vote or revocation of a prior proxy.

Beneficial owners of Encana common shares
may change their voting instruction only by submitting new voting instructions to the brokers, banks or other nominees that hold their shares of record. The time limit for the deposit of proxies may be waived or extended by the chair of the meeting
at his or her discretion without notice. In addition, shareholders who hold Encana common shares in an Encana employee benefit plan may revoke or change their proxy via any of the foregoing methods, except that a new employee benefit plan
participant proxy must be received by 8:00 a.m., Mountain Time, on February 4, 2019.

Registrar and Transfer Agent

The votes at the Encana special meeting will be counted by Encanas registrar and transfer agent, AST Trust Company (Canada).

Solicitation of Proxies

Encana will pay for the proxy solicitation costs related to the Encana special meeting. In addition to sending and making available these
materials, some of Encanas directors, officers and other employees may solicit proxies by contacting Encana shareholders by telephone, by mail, by e-mail or in person. Encana shareholders may also be
solicited by news releases issued by Encana and/or Newfield, postings on Encanas or Newfields websites and advertisements in periodicals. None of Encanas directors, officers or employees will receive any extra compensation for
their solicitation services. Encana has also retained MacKenzie Partners, Inc. and Kingsdale Advisors as its proxy solicitors to assist in the solicitation of proxies. For these proxy solicitation services, MacKenzie Partners will receive an
estimated fee of approximately $75,000 and Kingsdale Advisors will receive an estimated fee of approximately C$100,000, plus, in each case, reasonable out-of-pocket
expenses and fees for any additional services. Encana will also reimburse brokers, banks and other nominees for their expenses in sending proxy solicitation materials to the beneficial owners of Encana common shares and obtaining their proxies.

MacKenzie Partners is located at 1407 Broadway, 27th Floor New York, New York 10018 and can be contacted at 1-800-322-2885 toll free in North America, or at
+1-212-929-5500 outside of North America, or by e-mail at Encana@mackenziepartners.com.
Kingsdale Advisors is located at the Exchange Tower, 130 King Street West, Suite 2950, Toronto, Ontario, M5X 1E2 and can be contacted at
1-866-229-8166 toll free in North America, or at
416-867-2272 outside of North America, or by e-mail at contactus@kingsdaleadvisors.com.

Adjournments

The Encana special meeting may be adjourned in the absence of a quorum by the affirmative vote of a majority of votes cast by Encana
shareholders entitled to vote thereon and present in person or represented by proxy at the Encana special meeting.

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Even if a quorum is present, the Encana special meeting could be adjourned in order to
provide more time to solicit additional proxies in favor of approval of the share issuance proposal if a majority of votes are cast in favor of the Encana adjournment proposal. If after the adjournment a new record date is set for the adjourned
meeting, a notice of the adjourned meeting must be given to each shareholder of record entitled to vote at the Encana special meeting.

No Dissenters Rights

Under the CBCA, as well as the governing documents of Encana, the Encana shareholders are not entitled
to dissenters rights in connection with the merger or the transactions contemplated by the merger.

TSX
Disclosure

Under TSX rules, a company is generally required to obtain shareholder approval prior to the issuance of common shares if
the number of common shares to be issued is equal to or in excess of 25% of the number of common shares outstanding before the issuance of the common shares. If the merger is completed pursuant to the merger agreement, Encana expects to issue up to
547,430,751 Encana common shares, or approximately 57% of Encanas common shares outstanding as of November 29, 2018, in connection with the merger. Accordingly, the aggregate number of Encana common shares issuable upon the consummation
of the merger will exceed the threshold specified under TSX rules. TSX will generally not require further shareholder approval for the issuance of up to an additional 136,857,688 Encana common shares, such number being 25% of the number of Encana
common shares issuable in accordance with the share issuance proposal.

The issuance of Encana common shares pursuant to the merger is not
expected to have a material impact on the control of Encana.

Other Matters

At this time, Encana knows of no other matters to be submitted at the Encana special meeting.

Questions and Additional Information

Encana shareholders may contact Encanas proxy solicitors with any questions about the proposals or how to vote or to request additional
copies of any materials at:

1407 Broadway, 27th Floor

New York, New York 10018

Call Collect:
1-212-929-5500

Call Toll-Free:
1-800-322-2885

E-mail: Encana@mackeziepartners.com

130 King Street West, Suite 2950, P.O. Box 361

Toronto, Ontario M5X 1E2

Call Toll-Free (within North America):
1-866-229-8166

Call Collect (outside North America):
1-416-867-2272

E-mail: contactus@kingsdaleadvisors.com

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NEWFIELD SPECIAL MEETING

General

This
joint proxy statement/prospectus is being provided to Newfield stockholders as part of a solicitation of proxies by the Newfield board for use at the Newfield special meeting and at any adjournments or postponements of such special meeting. This
joint proxy statement/prospectus provides Newfield stockholders with information about the Newfield special meeting and should be read carefully in its entirety.

Date, Time and Place of the Newfield Special Meeting

The Newfield special meeting will be held on February 12, 2019 at the Four Seasons Hotel, Fairfield Ballroom, 1300 Lamar St., Houston,
Texas 77010 at 9:00 a.m., Central Time.

Purposes of the Newfield Special Meeting

The Newfield special meeting is being held to consider and vote upon the following proposals:



Proposal 1.To adopt the merger agreement, a copy of which is attached as Annex A to
this joint proxy statement/prospectus, pursuant to which each outstanding share of Newfield common stock (other than excluded shares) will be cancelled and converted into the right to receive 2.6719 Encana common shares with cash paid in lieu of the
issuance of fractional Encana common shares, if any (referred to previously in this joint proxy statement/prospectus as the merger agreement proposal);



Proposal 2. To approve, on an advisory (non-binding) basis,
the compensation that may be paid or become payable to Newfields named executive officers in connection with the merger (referred to previously in this joint proxy statement/prospectus as the non-binding
compensation advisory proposal); and



Proposal 3. To approve the adjournment of the Newfield special meeting, if necessary or
appropriate, to solicit additional proxies in favor of the merger agreement proposal if there are not sufficient votes at the time of such adjournment to adopt the merger agreement (referred to previously in this joint proxy statement/prospectus as
the Newfield adjournment proposal).

The Newfield board has (i) unanimously determined that the terms of the merger agreement and the transactions contemplated thereby,
including the merger, are advisable, fair to, and in the best interests of, Newfield and Newfield stockholders, (ii) unanimously approved and declared advisable the merger agreement and the transactions contemplated by the merger agreement,
including the merger, (iii) unanimously approved the execution and delivery by Newfield of the merger agreement, the performance by Newfield of its covenants and agreements contained therein and the consummation of the transactions contemplated
by the merger agreement, including the merger, upon the terms and subject to the conditions contained therein, (iv) unanimously directed that the merger agreement be submitted to Newfield stockholders at the Newfield special meeting to approve
its adoption, (v) taken all actions necessary so that the restrictions on business combinations and stockholder vote requirements contained in Section 203 of the DGCL and any other applicable law with respect to a moratorium,
control share acquisition, business combination, fair price or other forms of anti-takeover laws that may purport

54

to be applicable will not apply with respect to or as a result of the entry into the merger agreement and the consummation of the transactions contemplated thereby, including the merger, and
(vi) unanimously resolved to recommend that Newfield stockholders approve the adoption of the merger agreement.

This joint proxy
statement/prospectus contains important information regarding these proposals and factors that Newfield stockholders should consider when deciding how to cast their votes. Newfield stockholders are encouraged to read the entire document carefully,
including the annexes to and documents incorporated by reference into this joint proxy statement/prospectus, for more detailed information regarding the merger agreement and the merger.

The Non-binding Compensation Advisory Proposal and Interests of Directors

In considering the recommendations of the Newfield board, Newfield stockholders should be aware that some of Newfields directors and
executive officers may have interests that are different from, or in addition to, the interests of Newfield stockholders more generally. For more information see the section entitled The MergerInterests of Certain Newfield Directors and
Executive Officers in the Merger.

Section 14A of the Exchange Act, which was enacted as part of the Dodd-Frank Wall Street
Reform and Consumer Protection Act of 2010, requires that Newfield provide its stockholders with the opportunity to vote to approve, on an advisory (non-binding) basis, the compensation that may be paid or
become payable to Newfields named executive officers in connection with the merger, as disclosed in this joint proxy statement/prospectus, including the compensation table and the related narrative named executive officer compensation
disclosures set forth in The MergerInterests of Certain Newfield Directors and Executive Officers in the Merger. This vote is commonly referred to as a golden parachute say on pay vote. Accordingly, Newfield
stockholders are being provided with the opportunity to cast an advisory (non-binding) vote on those change of control payments.

Accordingly, Newfield is seeking approval of the following resolution at the Newfield special meeting:

RESOLVED, that Newfield stockholders approve, on an advisory (non-binding) basis, the
compensation that may be paid or become payable to Newfields named executive officers in connection with the Merger, as disclosed pursuant to Item 402(t) of Regulation S-K under the heading
The MergerInterests of Certain Newfield Directors and Executive Officers in the Merger (which disclosure includes the compensation table and related narrative named executive officer compensation disclosures required pursuant to
Item 402(t) of Regulation S-K).

Newfield stockholders should note that the non-binding compensation advisory proposal is merely an advisory vote which will not be binding on Newfield, Encana or their respective boards of directors. Further, the underlying plans and arrangements are
contractual in nature and not, by their terms, subject to stockholder approval. Accordingly, regardless of the outcome of the advisory vote, if the merger is consummated, the eligibility of the Newfield named executive officers for such payments and
benefits will not be affected by the outcome of the advisory vote.

The proposal to approve, on an advisory
(non-binding) basis, the compensation that may be paid or become payable to Newfields named executive officers in connection with the merger is a vote separate and apart from the vote on the proposal to
adopt the merger agreement. Accordingly, a Newfield stockholder may vote to approve one proposal and not the other. Because the vote on the proposal to approve, on an advisory (non-binding) basis, the
compensation that may be paid or become payable to Newfields named executive officers in connection with the merger is advisory in nature only, it will not be binding on Newfield or Encana, and the approval of that proposal is not a condition
to the completion of the merger.

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Attendance at the Newfield Special Meeting

Only Newfield stockholders of record as of the close of business on the record date, beneficial owners of Newfield common stock as of the close
of business on record date, holders of valid proxies for the Newfield special meeting and invited guests of Newfield may attend the Newfield special meeting.

All attendees should be prepared to present government-issued photo identification (such as a drivers license or passport) for
admittance. The additional items, if any, that attendees must bring depend on whether they are Newfield stockholders of record, beneficial owners of Newfield common stock or proxy holders.



a Newfield stockholder who holds shares of Newfield common stock directly registered in such stockholders
name with Newfields transfer agent, American Stock Transfer & Trust Company, LLC (a stockholder of record), who wishes to attend the Newfield special meeting in person should bring government-issued photo
identification.



a beneficial owner of Newfield common stock who wishes to attend the Newfield special meeting in person should
bring:



government-issued photo identification; and



proof of beneficial ownership as of the record date (e.g., a letter from the broker, bank, trustee or other
nominee that is the record owner of such beneficial owners shares, a brokerage account statement or the voting instruction form provided by the broker).



a proxy holder who wishes to attend the Newfield special meeting in person should bring:



government-issued photo identification;



the validly executed proxy naming such person as the proxy holder, signed by the Newfield stockholder; and



proof of the signing stockholders record ownership as of the record date.

No cameras, recording equipment or other electronic devices will be allowed in the meeting room. Failure to provide the requested documents at
the door or failure to comply with the procedures for the Newfield special meeting may prevent stockholders from being admitted to the Newfield special meeting.

Newfield is able to provide reasonable assistance to help persons with disabilities participate in the Newfield special meeting if Newfield is
notified in writing in advance of requested accommodations. Please write to Newfields principal executive offices at 4 Waterway Square Place Suite 100, The Woodlands, Texas 77380, Attention: Investor Relations.

Record Date

The record date for the determination of stockholders entitled to notice of and to vote at the Newfield special meeting is January 8, 2019.
Only Newfield stockholders who held shares of Newfield common stock at the close of business on January 8, 2019 are entitled to vote at the Newfield special meeting and any adjournment or postponement of the Newfield special meeting, so long as such
shares remain outstanding on the date of the Newfield special meeting.

Outstanding Shares as of Record Date

As of the record date, there were 200,933,274 shares of Newfield common stock outstanding, held by 1,299 holders of record. Each outstanding
share of Newfield common stock entitles its holder of record to one vote on each matter to be considered at the Newfield special meeting. Newfield common stock is the only class of shares entitled to vote at the Newfield special meeting, and
Newfield stockholders are entitled to vote on each proposal presented.

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A complete list of registered Newfield stockholders entitled to vote at the Newfield special
meeting will be available for inspection at the principal place of business of Newfield at 4 Waterway Square Place Suite 100, The Woodlands, Texas 77380, during regular business hours for a period of no less than ten (10) days before the
Newfield special meeting and at the place of the Newfield special meeting during the meeting.

Quorum

In order for business to be conducted at the Newfield special meeting, a quorum must be present. A quorum at the Newfield special meeting
requires the presence, in person or by proxy, of holders of a majority of the issued and outstanding shares of Newfield common stock entitled to vote at the Newfield special meeting. For purposes of determining whether there is a quorum, all shares
that are present, including abstentions, and entitled to vote will count towards the quorum.

Voting Rights of Newfield
Stockholders

Each outstanding share of Newfield common stock will be entitled to one vote on each matter to be considered at the
Newfield special meeting.

Vote Required

The votes required for each proposal are as follows:



Proposal 1the merger agreement proposal.The affirmative vote, in person
or by proxy, of the holders of at least 662⁄3% of the issued and outstanding shares of Newfield common stock entitled to vote on the merger agreement proposal as of
the record date for the Newfield special meeting is required to approve the merger agreement proposal. The failure of any Newfield stockholder to submit a vote (e.g., by not submitting a proxy or not voting in person), or any abstention, will
have the same effect as a vote against the merger agreement proposal. Because the merger agreement proposal is non-routine, brokers, banks and other nominees do not have discretionary authority to
vote on the merger agreement proposal, and will not be able to vote on the merger agreement proposal absent instructions from the beneficial owner.



Proposal 2the non-binding compensation advisory
proposal.The affirmative vote of a majority of votes cast by holders of the issued and outstanding shares of Newfield common stock entitled to vote on the non-binding compensation
advisory proposal and present in person or represented by proxy at the Newfield special meeting is required to approve the non-binding compensation advisory proposal. Abstentions will be considered shares of
Newfield common stock present and entitled to vote and will have the same effect as votes against the non-binding compensation advisory proposal. Brokers, banks and other nominees do not have
discretionary authority to vote on the non-binding compensation advisory proposal and will not be able to vote on the non-binding compensation advisory proposal. While
the Newfield board intends to consider the vote resulting from this proposal, the vote is advisory only and therefore not binding on Newfield or Encana, and, if the proposed merger with Encana is approved by Newfield stockholders and consummated,
the compensation will be payable even if the non-binding compensation advisory proposal is not approved.



Proposal 3the Newfield adjournment proposal.The affirmative vote of a
majority of votes cast by holders of the issued and outstanding shares of Newfield common stock entitled to vote on the Newfield adjournment proposal and present in person or represented by proxy at the Newfield special meeting is required to
approve the Newfield adjournment proposal. Abstentions will be considered shares of Newfield common stock present and entitled to vote and will have the same effect as a votes against the Newfield adjournment proposal. Brokers, banks and
other nominees do not have discretionary authority to vote on the Newfield adjournment proposal and will not be able to vote on the Newfield adjournment proposal absent instructions from the beneficial owner.

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If shares of Newfield common stock are held in the name of a broker, bank or other nominee,
the beneficial owner of such shares will receive separate instructions from his or her broker, bank or other nominee describing how to vote such shares.

A so-called broker non-vote results when banks,
brokers and other nominees return a valid proxy but do not vote on a particular proposal because they do not have discretionary authority to vote on the matter and have not received specific voting instructions from the beneficial owner of such
shares. Encana and Newfield do not expect any broker non-votes at the Encana special meeting or Newfield special meeting because the rules applicable to banks, brokers and other nominees only provide brokers
with discretionary authority to vote on proposals that are considered routine, whereas each of the proposals to be presented at the Encana special meeting and Newfield special meeting are considered
non-routine. As a result, no broker will be permitted to vote Encana common shares at the Encana special meeting or shares of Newfield common stock at the Newfield special meeting without receiving
instructions from the beneficial owner of such shares.

How to Vote

Newfield stockholders of record as of the close of business on the record date may have their shares of Newfield common stock voted by
submitting a proxy or may vote in person at the Newfield special meeting by following the instructions provided on the enclosed proxy card. Newfield recommends that Newfield stockholders entitled to vote submit a proxy even if they plan to attend
the Newfield special meeting.

Newfield stockholders who hold their shares of Newfield common stock beneficially in street
name and wish to submit a proxy must provide instructions to the broker, bank, trustee or other nominee that holds their shares of record as to how to vote their shares with respect to Proposals 1, 2 and 3. Newfield stockholders who hold their
shares of Newfield common stock beneficially and wish to vote in person at the Newfield special meeting must obtain proxies issued in their own names (known as a legal proxy).

Newfield stockholders of record may submit a proxy in one of three ways or vote in person at the Newfield special meeting:



Internet: Newfield stockholders may submit their proxy over the Internet at the web address shown on their
proxy card. Internet voting is available 24 hours a day and will be accessible until 11:59 p.m., Eastern Time, on February 11, 2019. Stockholders will be given an opportunity to confirm that their voting instructions have been properly
recorded. Newfield stockholders who submit a proxy this way should NOT send in their proxy card.



Telephone: Newfield stockholders may submit their proxy by calling the toll-free telephone number shown on
their proxy card. Telephone voting is available 24 hours a day and will be accessible until 11:59 p.m., Eastern Time, on February 11, 2019. Newfield stockholders who submit a proxy this way should NOT send in their proxy card.



Mail: Newfield stockholders may submit their proxy by properly completing, signing, dating and mailing
their proxy card in the postage-paid envelope (if mailed in the United States) included with this joint proxy statement/prospectus. Newfield stockholders who vote this way should mail the proxy card early enough so that it is received before the
date of the Newfield special meeting.



In Person: Newfield stockholders may vote in person at the Newfield special meeting or by sending a
representative with an acceptable proxy that has been signed and dated; attendance at the Newfield special meeting will not, however, in and of itself constitute a vote or a revocation of a prior proxy.

Newfield stockholders are encouraged to submit a proxy promptly. Each valid proxy received in time will be voted at the Newfield special
meeting according to the choice specified, if any. Executed but uninstructed proxies (i.e., proxies that are properly signed, dated and returned but are not marked to tell the proxies how to vote) will be voted in accordance with the
recommendations of the Newfield board.

Newfield stockholders who hold shares of Newfield common stock in Newfields 401(k) plan will
receive a separate voting direction card. The trustee of the Newfield 401(k) plan will vote such Newfield stockholders

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shares of Newfield common stock in accordance with the instructions on such stockholders returned direction cards.

For Newfield stockholders who hold shares of Newfield common stock in Newfields 401(k) plan who do not timely return a direction card or
return a direction card with no instructions, the trustee will vote the shares of Newfield common stock held by such Newfield stockholders in proportion to the voting directions received from all plan participants who properly vote.

Please note that the direction cards have an earlier return date than the proxy cards. Newfield stockholders who hold shares of Newfield
common stock in Newfields 401(k) plan should review their direction card for the date by which instructions must be received in order for such shares of Newfield common stock to be voted.

In the case of Internet or telephone voting, Newfield stockholders who hold shares of Newfield common stock in Newfields 401(k) plan
should have their direction card in hand and retain the card until they have completed the voting process. Newfield stockholders who hold shares of Newfield common stock in Newfields 401(k) plan who vote by Internet or telephone do not need to
return the direction card by mail.

Please note that no votes will be accepted at the Newfield special meeting in respect of shares of
Newfield common stock held in Newfields 401(k) plan and that all such votes must be voted prior to the Newfield special meeting.

Proxies and Revocation

Newfield stockholders of record may revoke their proxies at any time before their shares of Newfield common
stock are voted at the Newfield special meeting in any of the following ways:



sending a written notice of revocation to Newfield at 4 Waterway Square Place Suite 100, The Woodlands, Texas
77380, Attention: Investor Relations, which must be received before their shares are voted at the Newfield special meeting;



properly submitting a new, later-dated proxy card, which must be received before their shares are voted at the
Newfield special meeting (in which case only the later-dated proxy is counted and the earlier proxy is revoked);



submitting a proxy via the Internet or by telephone at a later date, which must be received by 11:59 p.m.,
Eastern Time, on February 11, 2019 (in which case only the later-dated proxy is counted and the earlier proxy is revoked); or



attending the Newfield special meeting and voting in person; attendance at the Newfield special meeting will not,
however, in and of itself, constitute a vote or revocation of a prior proxy.

Beneficial owners of shares of Newfield
common stock may change their voting instruction by submitting new voting instructions to the brokers, banks or other nominees that hold their shares of record or by requesting a legal proxy from such broker, bank or other nominee and
voting in person at the Newfield special meeting. In addition, stockholders who hold shares of Newfield common stock in Newfields 401(k) plan may revoke or change their proxy via any of the foregoing methods, except that a new 401(k) plan
participant proxy must be received by 11:59 p.m., Eastern Time, on February 8, 2019.

Solicitation of Proxies

Newfield will pay for the proxy solicitation costs related to the Newfield special meeting. In addition to sending and making available these
materials, some of Newfields directors, officers and other employees may solicit proxies by contacting Newfield stockholders by telephone, by mail, by e-mail or in person. Newfield stockholders may also
be solicited by news releases issued by Newfield and/or Encana, postings on Newfields or

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Encanas websites and advertisements in periodicals. None of Newfields directors, officers or employees will receive any extra compensation for their solicitation services. Newfield
has also retained Innisfree M&A Incorporated. to assist in the solicitation of proxies for a fee expected not to exceed $150,000, plus related fees for any additional services and reasonable out-of-pocket expenses. Newfield will also reimburse brokers, banks and other nominees for their expenses in sending proxy solicitation materials to the beneficial owners of Newfield common stock and
obtaining their proxies.

Adjournments

The Newfield special meeting may be adjourned by the chairman of the Newfield special meeting or by the affirmative vote of a majority of votes
cast by holders of the issued and outstanding shares of Newfield common stock entitled to vote at the Newfield special meeting and present in person or represented by proxy at the Newfield special meeting, regardless of whether there is a quorum,
without further notice other than by an announcement made at the Newfield special meeting. In the case that a quorum is not present at the Newfield special meeting, or in the case that a quorum is present at the Newfield special meeting but there
are not sufficient votes at the time of the Newfield special meeting to adopt the merger agreement, then the chairman of the Newfield special meeting has the power to adjourn the Newfield special meeting, or, alternatively, Newfield stockholders may
be asked to vote on a proposal to adjourn the Newfield special meeting in order to permit the further solicitation of proxies.

If the
adjournment is for more than thirty (30) days or if after the adjournment a new record date is set for the adjourned meeting, a notice of the adjourned meeting must be given to each Newfield stockholder of record entitled to vote at the
Newfield special meeting.

No Dissenter or Appraisal Rights

Because shares of Newfield common stock are listed on the NYSE and Newfield stockholders are not required to receive consideration other than
Encana common shares, which are listed on the NYSE, with cash paid in lieu of the issuance of fractional Encana common shares, if any, in the merger, Newfield stockholders are not entitled to exercise dissenters or appraisal rights under
Delaware law in connection with the merger.

Other Matters

At this time, Newfield knows of no other matters to be submitted at the Newfield special meeting.

Householding of Special Meeting Materials

Unless Newfield has received contrary instructions, Newfield may send a single copy of this joint proxy statement/prospectus and notice to any
household at which two or more stockholders reside if Newfield believes the stockholders are members of the same family. Each stockholder in the household will continue to receive a separate proxy card. This process, known as
householding, reduces the volume of duplicate information received at your household and helps to reduce Newfields expenses.

Questions and Additional Information

Newfield stockholders may contact Newfields proxy solicitor, Innisfree M&A
Incorporated with any questions about the proposals or how to vote or to request additional copies of any materials at:

Innisfree
M&A Incorporated

501 Madison Avenue, 20th Floor

New York, New York 10022

Call Toll-Free:
1-888-750-5834

Banks and Brokers Call Collect:
1-212-750-5833

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THE MERGER

This section of the joint proxy statement/prospectus describes the material aspects of the proposed merger. This section may not contain
all of the information that is important to you. You should carefully read this entire proxy statement/prospectus and the documents incorporated by reference into this joint proxy statement/prospectus, including the full text of the merger
agreement, a copy of which is attached to this joint proxy statement/prospectus as Annex A, for a more complete understanding of the proposed merger and the transactions related thereto. In addition, important business and financial information
about each of Encana and Newfield is included in or incorporated by reference into this joint proxy statement/prospectus and is included in the annexes hereto. See the section entitled Where You Can Find More Information.

Effects of the Merger

Upon satisfaction or waiver of the conditions to closing in the merger agreement, on the closing date, Merger Sub, an indirect wholly-owned
subsidiary of Encana formed for the purpose of effecting the merger, will merge with and into Newfield, whereby Newfield will be the surviving company in the merger as an indirect wholly-owned subsidiary of Encana. At the effective time, each share
of Newfield common stock issued and outstanding immediately prior to the effective time (other than excluded shares) will be cancelled and converted into the right to receive 2.6719 Encana common shares with cash paid in lieu of the issuance of
fractional Encana common shares, if any. In addition, Newfield will take all actions as may be necessary so that at the effective time, each outstanding restricted stock unit award or performance stock unit award in respect of Newfield common stock
will be treated as described in The MergerTreatment of Newfield Equity Awards in the Merger.

Background
of the Merger

The terms of the merger are the result of arms length negotiations between Encana and Newfield. The following is a
summary of the events leading up to the negotiation of the merger and the key meetings, negotiations, discussions and actions by and between Encana and Newfield and their respective advisors that preceded the public announcement of the merger.

Encanas decision to pursue a potential strategic combination with Newfield was the culmination of strategic analysis and study of the
Anadarko Basin and Newfield over several years. Commencing in 2013, Encana formed an internal multi-disciplinary group to undertake a major strategic review of the macro environment, industry dynamics and Encanas portfolio and to consider
various options that would generate long-term shareholder value. This initial strategic work, which targeted reshaping Encanas portfolio towards high-margin, liquids-weighted assets, was shared with investors in November 2013. Encana made
significant progress on its stated objectives in 2014. In 2015, Encana once again evaluated its progress and path forward through a strategic review conducted by a multi-disciplinary internal team. Supported by external advisors, this team intended
to challenge and further evolve Encanas strategy. As part of this work, Encana conducted in-depth technical reviews and evaluations of North Americas unconventional basins, in which STACK/SCOOP in
the Anadarko Basin was identified as a premium play with quality liquids-growth potential and significant scale. Technical experts within Encanas business development and strategy teams were directed to maintain an in-depth and on-going study of the Anadarko Basin. The findings of this analysis and recommendation were shared with Encanas board at its July 2015 annual strategy
session.

In the spring of 2016, having met the strategic goals set out in late 2013, Encanas management assembled another internal
multi-disciplinary strategy group to help shape the next five-year plan to grow shareholder value. This in-depth analysis, supported by the work of internal technical experts and external advisors, was
presented to Encanas board at its annual strategy session in July 2016. Encanas objectives to grow value through efficient development of liquids-focused high-margin production and to manage risk by focusing on a small number of
high-quality basins, was shared with investors in October 2016. As part of this 2016 work, Encana once again

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conducted an extensive review of a number of North American basins and identified Newfields position in STACK/SCOOP as one of five potential candidates for further study as a potential
inorganic growth option. Newfields premium position in the core of the oil window of STACK/SCOOP was a strong fit for Encanas high-margin, liquids-weighted objectives.

In July 2017, at the Encana boards annual strategy session, the Encana board discussed characteristics of a premium exploration and
production company with resiliency to deliver value to shareholders over the next decade. Those characteristics included a multi-basin portfolio to mitigate risks beyond Encanas control, a high quality liquids-weighted portfolio, scale to
drive efficiency and provide resiliency, the ability to grow and generate free cash flow and a strong balance sheet. Encanas management presented a number of organic and inorganic options to the Encana board and following its review, the
Encana board concluded that inorganic growth had to be accretive on a per-share basis and provide compelling full cycle returns to be considered.

Newfield was again identified by management among four inorganic opportunities for additional study. The Encana board recognized that
Newfields acreage would be an excellent fit for Encanas operating capabilities and technical expertise. However, based on Encanas view of Newfields positioning in the market, it was determined that Newfield would likely not
be interested in a transaction at such time and that any potential transaction would likely not meet Encanas requirements. The Encana board, therefore, determined that the timing was not right to approach Newfield regarding a potential
transaction. Through the remainder of 2017 and early 2018, Encanas management continued to provide additional analysis to the Encana board on Newfield and three other possible candidates, eliminating two of the candidates due to portfolio fit,
valuation, full cycle returns and other factors, including the lack of immediate accretion to Encanas shareholders.

The Newfield
board and Newfield executive management team regularly review Newfields operating results, capital structure, future growth opportunities and competitive position in the exploration and production industry. These reviews have included
consideration by Newfields management and board, and discussions with industry participants from time to time, of potential strategic alternatives, including acquisitions, joint ventures and business combinations or other strategic
transactions, as well as ongoing initiatives aimed at enhancing shareholder value and growing Newfield organically, to prepare for and respond to changing market forces and resulting business risks and uncertainties in the exploration and production
industry.

During its July 26-27, 2018 board meeting, as part of Newfields ordinary course
evaluation of its strategic direction, the Newfield board evaluated the significant structural changes in the exploration and production industry since the 2014 downturn and the numerous variables impacting the future for exploration and production
companies. The general consensus of the Newfield board was that the exploration and production industry was at a crossroads  shifting from the capture and assessment of large-scale onshore resource plays to the ultimate development of these
plays, and focusing on sustainable free cash flow generation and growth. As a result of this shift, significant synergies and value could be achieved through scale, the swift application of leading drilling and completion technologies, the
unbundling of services at the field level and improved access to downstream markets for oil, NGLs and natural gas. In addition to the changes within the exploration and production industry, the Newfield board also discussed investor feedback for
improved efficiencies (much like other manufacturing sectors) and emphasis on total shareholder return and sustainable free cash flow generation allowing for a return of cash to owners through dividends and share buybacks.

As part of its evaluation of Newfields strategic direction, the Newfield board discussed a number of potential strategic alternatives,
including: (i) continuing on its current path as a standalone company while shifting capital expenditures among its current basins and formations to capture the highest margins, returns and value opportunities in response to ongoing market
volatility and investor concerns; (ii) acquiring one or more exploration and production companies or assets to enhance Newfields scale and competitiveness in an increasingly volatile market; or (iii) entering into a business
combination with a similarly-sized or larger exploration and production company. The Newfield board discussed these potential paths in depth, including the relative merits of each option in relation to
providing attractive economies of scale, improved free cash flow and

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a return of capital to Newfields investors. At the conclusion of its meetings, the Newfield board determined that it would be useful for Mr. Lee K. Boothby, Newfields
Chairman, President and Chief Executive Officer, to have conversations over the course of the coming months with other similarly situated companies in the exploration and production industry to discuss broader trends and the potential for industry
consolidation. The purpose of these discussions was to gather additional information on industry conditions to help inform the Newfield boards discussions at its annual strategy session planned for late October 2018.

Following the July 26-27, 2018 board discussions, Mr. Boothby had informational meetings with
seven exploration and production companies, including Encana. Mr. Boothby kept the other members of the Newfield board informed on the content of these discussions.

On July 30-31, 2018, the Encana board held its annual strategy session where they re-tested their analysis of the elements of a premium North American exploration and production company. Encanas management provided an overview of various North American basins and highlighted the in-depth reviews that management and its technical teams, along with external advisors, had conducted since 2013. Encanas management noted that over the past two years, it had presented to the Encana board a
number of organic and inorganic options, and that it became apparent through its ongoing technical reviews that an entry into STACK/SCOOP in the Anadarko Basin had more compelling full-cycle returns relative to other basins Encana management had
studied. This updated evaluation also confirmed that STACK/SCOOP, and Newfields position in the oil window, provided an opportunity for quality liquids growth potential with competitive returns, good access to markets, scale and running room
to apply Encanas cube development approach. Encanas management outlined its extensive review of Newfield based on publicly available information. The Encana board then discussed the benefits of a possible transaction with
Newfield, including the ability to grow and generate material free cash flow at attractive valuations, and that this could be a unique and immediately accretive combination. Following a discussion by the Encana board, it was agreed that
Mr. Douglas J. Suttles, Encanas President & Chief Executive Officer, should approach Mr. Boothby to determine whether Newfield may be interested in exploring a potential strategic combination with Encana.

On September 10, 2018, at the request of Mr. Suttles, Messrs. Boothby and Suttles had dinner in The Woodlands, Texas. At the dinner,
they shared views on the characteristics of a premium exploration and production company and noted similarities in their views. Messrs. Boothby and Suttles then discussed Newfields and Encanas operations and core geographies and the
views of their respective boards on their respective strategic paths. Mr. Boothby noted that scale and competitiveness in an increasingly volatile market would be important, but in a review of potential acquisition candidates, Newfield had not
identified a candidate it was prepared to pursue. Mr. Suttles then asked Mr. Boothby whether Newfield would be interested in exploring a potential strategic combination, in which Encana would acquire all of the issued and outstanding
shares of Newfield common stock. Mr. Boothby indicated that Newfield may be interested in engaging in such discussions at an appropriate time following the Newfield board meeting and planned annual strategy session in late October 2018. Shortly
thereafter, Mr. Boothby reported the conversation to Newfield directors, Mr. Steven W. Nance (lead director) and Mr. J. Terry Strange.

On or about September 17, 2018, Mr. Suttles contacted Mr. Boothby to reiterate Encanas interest in exploring a potential
strategic combination of Encana and Newfield.

In early October, Mr. Boothby saw Mr. Suttles at an industry event and told
Mr. Suttles that he would be in Denver, Colorado on October 8, 2018. Mr. Suttles proposed a lunch meeting, at which they could continue their earlier discussions. Mr. Boothby reiterated that the Newfield board would be holding
its regularly scheduled meeting and strategy discussions in late October 2018 and that any substantive discussions regarding a strategic combination would be best placed to occur after the conclusion of those meetings.

On October 8, 2018, Messrs. Boothby and Suttles had lunch in Denver, Colorado. At lunch, Mr. Boothby indicated that, based on prior
discussions with the Newfield board, it was unlikely they would be interested in

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any transaction that did not reflect, at a minimum, a customary premium in similar transactions understood to be a premium of at least 25% to Newfields then-current stock price, which would
have represented an implied offer price of $35.40 per share of Newfield common stock using Newfields closing stock price on October 5, 2018. Mr. Suttles indicated that he would discuss Mr. Boothbys feedback with
Encanas board and, if Encana was prepared to proceed, any proposal would be subject to conducting due diligence of Newfield, the execution of a confidentiality agreement, including customary standstill provisions, and the execution of an
exclusivity agreement.

That same day, Mr. Boothby met for dinner with the chief executive officer of another exploration and
production company (which we refer to as Company A), during which they discussed general trends in the industry, including the potential for industry consolidation (without reference to specific transactions involving the two companies).

On October 9, 2018, Mr. Suttles indicated by phone call to Mr. Boothby that Encana would be having an Encana board meeting
the following day and would discuss sending a non-binding proposal to Newfield. Mr. Boothby reported this call to Mr. Nance.

On the morning of October 10, 2018, Mr. Boothby met in person with the chief executive officer of another exploration and production
company (which we refer to as Company B), during which they discussed general trends in the industry, including the potential for industry consolidation (without reference to specific transactions involving the two companies).

Also on October 10, 2018, the Encana board met to discuss the proposed strategic combination of Encana and Newfield, including the
potential merits and risks of such a combination. At the meeting, Mr. Suttles updated the Encana board on the status of discussions with Newfield. Encana management then discussed potential transaction alternatives, valuations of Newfield and
key deal terms for a potential offer. Encanas board discussed the relative valuations of the companies and noted that a transaction could be opportunistic if done in a timely manner given current equity market conditions, its premium position
in STACK/SCOOP and Encana managements confidence in delivering on operational results and synergies. Encanas management also reviewed its legal and commercial views based on publicly available information. Following discussion among the
Encana board members, it was agreed that Encana would submit a non-binding proposal to acquire all of the issued and outstanding shares of Newfield common stock in exchange for a combination of cash and Encana
common shares.

Later that day, Encana submitted a non-binding proposal to Newfield, which
contemplated the acquisition of all of the issued and outstanding shares of Newfield common stock by Encana for aggregate consideration consisting of $1.0 billion in cash and 470,200,000 Encana common shares, which, based on Newfields
public disclosure of the number of shares of Newfield common stock outstanding as of June 30, 2018 (excluding long-term incentives), represented an implied offer price of $35.00 per share of Newfield common stock, using the 20-day volume weighted average price of Encanas common shares on October 9, 2018; the implied offer price per share represented a 24% premium to Newfields closing stock price on October 9,
2018. The non-binding proposal described certain key deal terms, including a non-solicitation provision with a fiduciary out, a
five-day matching right, a Newfield termination fee of 4.5% (based on Newfields equity value), and that the proposal was subject to due diligence between the companies, as well as a period of exclusive
negotiations between Encana and Newfield expiring on October 31, 2018.

After receiving the
non-binding proposal, Messrs. Boothby and other members of Newfield management spoke with Mr. Suttles over the phone to discuss the proposals key terms. Mr. Suttles also indicated that Encana
would provide a draft confidentiality agreement for Newfields review, as well as a list of due diligence items to facilitate Encanas preliminary due diligence review. Messrs. Boothby and such other members of Newfield management reported
the results of their discussion with Mr. Suttles to Mr. Nance.

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On October 11, 2018, Mr. Boothby contacted Kirkland & Ellis LLP
(Kirkland) and Wachtell, Lipton, Rosen & Katz (Wachtell and, together with Kirkland, Newfields outside counsel) to assist Newfield in considering a potential combination with Encana or others. Over
the next few days, Newfields outside counsel worked with representatives of Newfield to assess Encanas proposal and to conduct due diligence of Encanas publicly available information.

On October 14, 2018, the Newfield board met telephonically to discuss Encanas proposal. Certain members of Newfield management and
representatives of Newfields outside counsel were also in attendance. At the meeting, Mr. Boothby updated the Newfield board on recent discussions with each of Encana, Company A and Company B, and preliminary perspectives on a potential
combination with Encana. Representatives of Newfields outside counsel reviewed with members of the Newfield board their fiduciary duties in considering and responding to the proposal made by Encana and in determining whether to approve a
strategic transaction, like that proposed by Encana.

The Newfield board discussed the attractive attributes of the combined company,
including substantial scale and an expanded multi-basin portfolio, liquids-rich production mix, significant operational and corporate synergies, asset quality, lower cost of capital and an investment grade financial profile. The general similarities
between Encana and Newfield with regard to their relative splits between oil and gas production were also discussed. The Newfield board noted that the combined company would create one of the largest producers and acreage holders of unconventional
onshore liquids-rich resources in North America, with an accompanying opportunity for incremental value creation if the combined company were able to effectively utilize the economies of scale and synergies that could be generated by the merger. The
Newfield board also discussed potential risks and concerns associated with the proposed combination and also considered the specific terms of the Encana proposal, including whether the proposal accurately reflected the relative valuation of the two
companies and whether the proportional split of cash and stock being offered was appropriate. Following these discussions, the Newfield board determined that Encanas proposal had the potential to result in a compelling transaction for
Newfield. In addition, the Newfield board determined that entry into an exclusivity agreement with Encana was not in the companys best interest at the time.

The Newfield board authorized Newfields management and advisors to proceed with a due diligence review of the potential merger with
Encana and to seek improved economic terms. The Newfield board also authorized the engagement of J.P. Morgan and Goldman Sachs & Co. (Goldman Sachs) to serve as Newfields financial advisors for a potential strategic transaction
or transactions. The Newfield board asked J.P. Morgan to provide a fairness opinion with respect to such a transaction or transactions and Goldman Sachs to provide Newfield with advice on general market conditions, consideration mix evaluation,
pro forma credit impact and other related matters, subject, in each case, to disclosure by each firm of its relationships with Encana or any other potential purchaser and evaluation of any conflicts by the Newfield board with the advice of its
outside counsel.

Pursuant to the direction of the Newfield board, Newfield contacted J.P. Morgan and Goldman Sachs to engage them in
connection with a possible transaction. Neither J.P. Morgan nor Goldman Sachs were authorized to, and did not solicit, any expressions of interest from any other parties with respect to the sale of all or any part of Newfield or any other
alternative transaction. In addition, Goldman Sachs was not requested to provide, and did not provide, any opinion as to the fairness of any proposed transaction or any valuation for the purposes of assessing the fairness of the consideration in any
proposed transaction.

On October 15, 2018, Mr. Boothby conveyed to Mr. Suttles the view of the Newfield board that the
consideration being offered in the proposed merger required further discussion. Although the Newfield board was willing to enter into a mutual confidentiality agreement with Encana and begin exchanging confidential information for due diligence,
Newfield was not prepared to execute an exclusivity agreement. Mr. Suttles reiterated Encanas continued interest in exploring a transaction and advised Mr. Boothby that Encana had engaged legal and financial advisors, and, if
Newfield was prepared to negotiate a transaction in a timely manner, an exclusivity agreement would not be required. Mr. Suttles indicated that Encana would provide a list of preliminary due diligence items.

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On October 16, 2018, Messrs. Boothby and Suttles spoke regarding the proposed
confidentiality agreement, scheduling mutual management presentations and other matters. Following negotiation of the draft confidentiality agreement between Encanas legal advisor, Paul, Weiss, Rifkind, Wharton & Garrison LLP
(Paul Weiss) and Kirkland, the parties executed the confidentiality agreement on October 16, 2018, which included customary reciprocal standstill provisions. Following the execution of the confidentiality agreement,
Encana and Newfield began to share confidential information in order to facilitate due diligence review.

On October 17, 2018,
Encanas financial advisors, Credit Suisse, which had been providing advice to Encana over a period of time on its strategic analysis, and TD Securities contacted Newfields financial advisor, J.P. Morgan, to discuss the potential
transaction.

The Newfield board met telephonically on October 18, 2018, during which the board members further discussed the
engagement of J.P. Morgan and Goldman Sachs in connection with a proposed transaction. Certain members of Newfield management and representatives of Newfields outside counsel were also in attendance. Mr. Boothby provided the Newfield
board with initial information on pre-existing relationships between J.P. Morgan and Encana, and after discussion, the board concluded that, based on such initial information, the pre-existing relationship was immaterial and did not create a
conflict that should call into question the independence of J.P. Morgans advice to the Newfield board. The Newfield board also discussed the specific proposal received from Encana and the broader question of whether another third party,
including Company A or Company B, would potentially be a more attractive merger partner. The Newfield board directed that Goldman Sachs, once engaged, should provide guidance to the Newfield board on potential alternative counterparties to a
strategic transaction. The Newfield board also engaged in a discussion of the commercial terms of a merger agreement with Newfields outside counsel, including the termination fee set forth in the
non-binding proposal as compared to market practice.

On the evening of October 18, 2018,
Paul Weiss delivered to Kirkland an initial draft of the merger agreement. The draft contemplated, among other things: (i) a taxable transaction in which an indirect wholly-owned subsidiary of Encana would acquire all of the issued and
outstanding shares of Newfield common stock for cash and Encana common shares; (ii) non-solicitation provisions applicable to Newfield that would allow the Newfield board, under certain circumstances, to
change its recommendation in the event of a superior proposal or intervening event and to terminate the merger agreement to accept a superior proposal; (iii) a termination fee equal to 4.5% of Newfields equity payable by Newfield in the
event the agreement was terminated as a result of a superior proposal or following a change in recommendation; and (iv) expense reimbursement equal to 1.0% of Newfields equity value payable by Newfield or Encana to the other party in the
event its stockholders or shareholders, as applicable, did not approve the adoption of the merger agreement or the issuance of Encana common shares, as applicable. Newfields outside counsel discussed these terms and other provisions of the
draft merger agreement with representatives of Newfield on several occasions over the following days.

On the morning of October 19,
2018, the chief executive officer of Company B contacted Mr. Boothby and informed him that Company B was interested in exploring next steps in connection with a strategic transaction between Newfield and Company B, indicating that Company B
would send a proposal to Newfield later that week.

Later that day, J.P. Morgan provided written disclosure to Newfield of such
advisors relationships with Encana and its affiliates, which relationships are summarized more fully in The MergerOpinion of Newfields Financial Advisor. The Newfield board subsequently concluded that based on such
disclosures the pre-existing relationship between J.P. Morgan and Encana was immaterial and did not create a conflict that should call into question the independence of J.P. Morgans advice to the Newfield board.

On October 20, 2018, Mr. Boothby met with Mr. Suttles to discuss certain key concerns regarding the draft merger agreement,
including, among others, the need for less restrictive non-solicitation provisions, the size of the termination fee and the circumstances under which the termination fee would be payable by Newfield, the

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need for reciprocal representations, warranties and interim operating covenants applicable to Encana, board representation for Newfield on the Encana board post-closing, the need for continuity
of benefits for Newfield employees, treatment of certain Newfield long-term incentives and the proposed taxable nature of the transaction.

On the evening of October 20, 2018, Encana and its advisors were provided with access to Newfields electronic data room compiled
based on information requests Encana had previously delivered to Newfield. From October 20, 2018 to October 31, 2018, Encana, with the assistance of its advisors, conducted a business, technical, accounting, tax and legal due diligence
review of Newfield through Newfields electronic data room, additional requests for information and due diligence calls with relevant Newfield experts and advisors.

The Newfield board held a telephonic meeting on October 21, 2018. Certain members of Newfield management and representatives of
Newfields outside counsel were also in attendance. During the meeting, representatives of Newfields outside counsel provided an overview of the key terms of the merger agreement and an update on the status of the legal review of
materials provided by Encana. J.P. Morgan and Goldman Sachs each provided the Newfield board with a general overview of the market and industry trends, a discussion of Encanas financial position based on publicly available information and
other related information.

In discussing trends in the exploration and production industry, the Newfield board noted that several key
macro-level factors weighed in favor of pursuing a combination at this time, though recent volatility in both equity markets and commodity prices could have a dampening effect on strategic activity generally. As it had in July 2018, the Newfield
board noted that the industry remained in significant transition, generally shifting away from a primary focus on acreage accumulation and assessment toward a business model that more closely resembled traditional manufacturing sectors. This
transition, combined with increasing investor focus on operational and cost efficiencies as well as return of capital to equityholders, would likely lead to increased industry consolidation and could provide a compelling opportunity for Newfield and
its stockholders. Most notably, the Newfield board recognized that Encana had seen successful results with its cube development application within its Permian Basin operations, which Newfield had begun implementing in recent quarters in
certain basins. The board recognized that Encana was ahead of Newfield in regards to the application of cube development.

Mr. Boothby also provided the Newfield board with an update on his recent discussion with the chief executive officer of Company B.
Mr. Boothby also informed the Newfield board that he expected a request for a follow-up meeting from the chief executive officer of Company A to discuss a possible strategic transaction between Company A
and Newfield.

On October 22, 2018, members of Encanas management, as well as a representative from Credit Suisse, attended a
meeting in The Woodlands, Texas with Newfields management, as well as representatives from J.P. Morgan and Goldman Sachs, and each of Encana and Newfield presented an overview of its respective asset base, strategic direction and
financial outlook. The parties engaged in a discussion on the merits of a strategic transaction and the potential synergies that could be achieved by a combination of the two companies.

That same day, representatives of Encana management prepared a revised, consolidated due diligence request list, which was delivered to
Newfields outside counsel and representatives of Newfield.

Also on October 22, 2018, Newfield and its advisors were provided
with access to Encanas electronic data room, which was compiled based on information requests Newfield had previously delivered to Encana. From October 22, 2018 to October 31, 2018, Newfield and its advisors conducted business,
technical, accounting, tax and legal due diligence of Encana, and Newfields advisors provided periodic updates to the Newfield board and Newfield management regarding the findings of their due diligence review during that time.

On October 23, 2018, Messrs. Boothby and Suttles discussed their mutual interest in further progressing discussions on the potential
transaction following the prior days management presentations.

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On October 24, 2018, Kirkland delivered a revised draft of the merger agreement to Paul
Weiss, reflecting Newfields comments on the October 18, 2018 draft, to, among other things: (i) restructure the transaction to be a tax-deferred reorganization; (ii) make the
representations, warranties and covenants of the parties reciprocal, including with respect to the non-solicitation provisions and related termination rights; (iii) decrease the termination fee to 2% of
Newfields equity value, which would be payable upon the occurrence of certain events described in the merger agreement; (iv) revise the non-solicitation provisions of the parties to enable
additional flexibility to consider an alternative proposal; (v) specify the treatment of certain executive compensation matters; (vi) provide for continuity of employee benefits; and (vii) permit Newfield to designate an unspecified
number of directors to the Encana board following closing.

That same day, the parties held a series of due diligence calls involving
Encana, Newfield, Paul Weiss and Kirkland.

Also on October 24, 2018, Goldman Sachs provided written disclosure to Newfield of its
relationships with Encana. Such disclosure stated, among other things, that as of that date, none of Goldman Sachss Investment Banking Division, funds in which Goldman Sachss Investment Banking Division has a direct investment, Goldman
Sachss Merchant Banking Division or funds managed by Goldman Sachss Merchant Banking Division, had a direct investment in the equity securities of Newfield or Encana. In addition, one or more affiliates of Goldman Sachs is a lender under
outstanding credit facilities of Newfield and certain affiliates of Encana, has acted as counterparty to Newfield and Encana on energy-related derivative exposures and has provided certain advisory services to Encana.

In the early afternoon of October 24, 2018, Mr. Boothby received a telephone call from another exploration and production company
active in one of the basins in which Newfield also operates (which we refer to as Company C) to discuss a potential acquisition of Company C by Newfield. Mr. Boothby indicated to the chief executive officer of Company C that he
would like to delay discussion of such a transaction until after Newfields regularly-scheduled board and strategy session in late October.

That evening, Mr. Boothby met with the chief executive officer of Company A, during which they discussed the conceptual framework for a
strategic transaction between Newfield and Company A. The chief executive officer of Company A indicated that any such transaction would need to be structured as a merger of equals with little or no premium.

During this time, Newfield, Encana and their respective advisors continued their legal and financial reviews of each other, including in-person reviews of board minutes of the two companies and certain of their respective subsidiaries and telephone calls between Newfield, Kirkland, Encana and Paul Weiss regarding certain regulatory diligence
matters.

On October 25, 2018, Paul Weiss delivered a revised merger agreement to Kirkland, accepting certain changes in the draft
Kirkland had delivered to Paul Weiss the previous day, but increasing the termination fee to 4% of Newfields equity value, revising the definition of superior proposal, modifying the interim operating covenants and treatment of executive
compensation matters and proposing that Newfield would designate one director, mutually agreed by the parties, to the Encana board following closing.

Also on October 25, 2018, Encanas management reviewed with Encanas internal due diligence team the preliminary results of
their due diligence investigations of Newfield, along with potential synergies.

That same day, the Newfield board met in person to
discuss, among other things, the current status of the legal and financial review of Encana and the status of the merger agreement, and to receive presentations from the financial advisors on Encana and the proposed transaction with Encana. Certain
members of Newfield management and representatives of Newfields outside counsel were also in attendance. Goldman Sachs presented on the market and industry generally, including recent public exploration and production strategic transactions.
Goldman Sachs also commented on potential alternative counterparties to a strategic transaction

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with Newfield, noting that the universe of such counterparties was few in number and likely would not offer the same scale and asset quality as Encana. Goldman Sachs also provided the Newfield
board with an overview of Encanas operations and financial position and discussed with the board certain strategic, operational and financial considerations with respect to the proposed transaction with Encana.

J.P. Morgan then presented on the proposed transaction to the Newfield board, noting recent volatility in both the energy sector and broader
stock market in general, during which time Encana shares and Newfield stock had often traded out of sync with each other, and that the initial implied premium had increased from the implied premium on October 10, 2018, the date Encana delivered
its initial proposal to Newfield. The Newfield board discussed with both financial advisors the current volatility in equity markets and commodity markets generally and the impact such volatility is having on strategic transaction activity overall,
including the limited availability of potential alternative counterparties to a strategic transaction with Newfield. The Newfield board also discussed various positive and negative aspects of the potential combination with Encana, including
Encanas free cash flow yield and balance sheet, the large, contiguous acreage positions of both companies and the multi-basin diversification and economies of scale the combined company would offer, the increased potential for return of
capital to shareholders, Encanas relative splits between production from oil versus gas and certain other factors.

The Newfield
board also reconsidered the merits of Newfield continuing as a standalone entity in an industry undergoing significant transition, in which scale and the ability to generate significant free cash flow are expected to create meaningful value for
stockholders. Finally, the Newfield board considered potential strategic transactions with other third parties previously identified by Newfield in connection with its review of its strategic options and discussed whether any such alternative
transactions would be available or attractive given the broader volatility in the markets in recent days and weeks.

Following these
presentations and discussions, Mr. Boothby provided the Newfield board with an update on discussions with third parties, including his discussions with Company A and Company C. The Newfield board noted that a transaction with Company A would
contain little or no premium according to Company As chief executive officer and that any such transaction would not result in the same strategic benefits or economies of scale as expected in the Encana transaction. The Newfield board
separately noted that the acquisition of Company C would not provide the necessary economies of scale in the current industry environment and would result in a less favorable credit profile. Mr. Boothby indicated that he had not had any contact
with Company B since October 19, 2018. The Newfield board then instructed Newfield management to continue discussions with Encana, while noting that any such combination could be impacted by recent equity and commodity price volatility.

The Newfield board also discussed certain key items in the merger agreement, including Encanas right to terminate the merger agreement
in certain circumstances and the appropriate amount of Encanas termination fee, certain compensation items, the tax treatment of the merger and representation rights on Encanas board post-closing.

On October 26, 2018, Mr. Boothby contacted Mr. Suttles to arrange to meet in The Woodlands, Texas for dinner following the
Newfield board meeting on October 28, 2018. Messrs. Boothby and Suttles also discussed the current status of definitive documentation, coordination of communications in connection with the potential announcement of a transaction, should that
occur, as well as the impact of recent market volatility on the implied premium.

On October
26-27, 2018, Kirkland and Paul Weiss exchanged emails and telephone calls regarding comments to and revised drafts of the merger agreement and continued to negotiate specific items in the merger agreement.

On October 28, 2018, the Newfield board met in person to discuss the status of Newfields review of Encana and the proposed
transaction further with its financial and legal advisors. Certain members of Newfield

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management were also in attendance. Newfield management presented on the results of its financial review of Encana and noted that it had not identified any areas of material concern. For more
information on the projections prepared, or otherwise authorized for use, by Encana, see the section entitled The MergerCertain Encana Unaudited Prospective Financial and Operating Information.

Representatives of Goldman Sachs provided an update to the Newfield board on market and industry conditions, including a discussion of the
impact of changes in commodity pricing, as well as additional detail on recent exploration and production mergers, including announced synergies. J.P. Morgan separately presented its preliminary financial analysis of Newfield, Encana and the
proposed merger to the Newfield board. J.P. Morgan also presented on certain pro forma expected benefits of the combined company. The Newfield board engaged in a discussion with J.P. Morgan regarding the assumptions and methodologies used in the
preparation of this analysis.

Representatives of Goldman Sachs and J.P. Morgan also presented separately on their existing relationships
with Encana, consistent with the written disclosure each had previously provided to Newfield. The Newfield board determined (or, in the case of J.P. Morgan, reaffirmed its prior determination) that the existing relationships of Goldman Sachs and
J.P. Morgan with Encana were immaterial and did not create a conflict that should call into question the independence of the advice either financial advisor was providing to the Newfield board.

Representatives of Newfields outside counsel presented on the status of their legal due diligence review of Encana and the merger
agreement. Members of the Newfield board engaged in discussions with the representatives of Newfields outside counsel regarding certain key terms in the merger agreement, including the non-solicitation
provisions, termination fee triggers, the amount of termination fees and certain compensation-related matters. Representatives of Newfields outside counsel also reviewed the Newfield boards fiduciary obligations in connection with a
potential strategic transaction and responded to questions from board members.

On October 28, 2018, Mr. Suttles travelled to
The Woodlands, Texas and met Mr. Boothby for dinner. At dinner, Messrs. Boothby and Suttles discussed certain outstanding deal terms, including the consideration to be offered to Newfield stockholders in connection with the proposed
transaction, the proposed tax treatment of the merger, Newfields right to designate directors to Encanas board following closing of the proposed transaction, the termination provisions in the merger agreement and certain employee
matters. Mr. Suttles advised Mr. Boothby that because Newfields stock price had declined since Encanas non-binding proposal was made on October 10, 2018, the consideration cited in
the non-binding proposal would need to be adjusted. While Messrs. Boothby and Suttles reserved discussion on revised consideration terms, Messrs. Boothby and Suttles agreed on certain other outstanding items,
including that Newfield would designate two directors, reasonably agreeable to both parties, to the Encana board following closing of the merger. Mr. Boothby further advised Mr. Suttles that Newfields compensation committee had
ongoing deliberations regarding certain compensation matters that were previously under review. At the end of the dinner, Mr. Boothby indicated that he would need to discuss the other outstanding items with the Newfield board.

On the morning of October 29, 2018, Mr. Boothby met Mr. Suttles in The Woodlands, Texas to discuss the merger consideration,
including a possible reduction in the amount of cash being offered in exchange for an increased percentage ownership of Newfield stockholders in the combined company post-closing. Mr. Boothby noted that the Newfield board was continuing its
meetings later that day and following such meetings they could discuss further.

Later that day, Paul Weiss delivered a revised draft of
the merger agreement to Newfields outside counsel, following which Paul Weiss and Kirkland engaged in discussions on the outstanding issues in the merger agreement. Messrs. Boothby and Suttles also spoke during the day on certain outstanding
items, including the termination fee triggers, amount of termination fees and certain employee-related matters.

The Newfield board met
again on October 29, 2018. Certain members of Newfield management and representatives of Newfields outside counsel were also in attendance. J.P. Morgan presented on certain attributes

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of the pro forma company. The Newfield board then engaged in separate discussions with representatives of J.P. Morgan and Goldman Sachs regarding the relative merits of an all-stock versus mixed consideration deal. Following this discussion, it was the general consensus of the Newfield board that, in light of continued market volatility, an
all-stock deal would enable Newfield stockholders to capture more of the expected upside of the combined company, rather than crystalizing a portion of the consideration in cash, and that retaining the cash to
be used for the merger consideration on the combined companys balance sheet (which could potentially be available to return to shareholders in the form of increased dividends or share buybacks post-closing) could be advantageous for the
combined company and its shareholders. The Newfield board discussed the appropriate relative pro forma ownership of the combined company and authorized Mr. Boothby to propose to Mr. Suttles an all-stock deal with Newfields current stockholders
owning, in the aggregate, at least 38% of the issued and outstanding Encana common shares following the closing of the proposed transaction.

Representatives from Newfields outside counsel also presented to the Newfield board on the proposed tax treatment of the transaction.
Following discussion, the Newfield board determined that a taxable transaction likely would not have a significant negative impact on Newfields stockholders, taken as a whole (but acknowledged it could possibly have a negative impact on a few
Newfield stockholders), but it would enable Encana to obtain full tax basis in the shares of common stock of Newfield for the benefit of the combined companys shareholders in the future.

The Newfield board also discussed the relative termination fees payable by Newfield and Encana in certain situations and it was the general
consensus of the Newfield board that the termination fees payable by each of Newfield and Encana should be proportional to its size.

Finally, Mr. Boothby updated the Newfield board on his most recent discussion with the chief executive officer of Company B.
Mr. Boothby summarized for the Newfield board the discussions with Company B to date, including Mr. Boothbys initial informational meeting with the chief executive officer of Company B on October 10, 2018 and the call from the
chief executive officer of Company B on October 19, 2018, in which the chief executive officer expressed interest in a potential strategic transaction with Newfield and informed Mr. Boothby that a proposal would be forthcoming.
Mr. Boothby then informed the Newfield board that he had received a call from the chief executive officer of Company B on October 29, 2018, in which the chief executive officer stated that Company B would not be providing a written
proposal for a strategic combination of Company B and Newfield, noting that any such proposal would have been unlikely to be actionable on a similar timetable as the transaction proposed by Encana and would have been subject to customary conditions
and diligence.

On the evening of October 29, 2018, Messrs. Boothby and Suttles spoke by telephone and discussed the transaction
consideration as well as other outstanding items. Mr. Boothby proposed to Mr. Suttles that the Newfield board would be interested in pursuing an all-stock transaction if Newfields current
stockholders would own, in the aggregate, at least 38% of the issued and outstanding Encana common shares following the closing of the proposed transaction. Based on information provided by Newfield on the number of shares of Newfield common stock
issued and outstanding, including long-term incentives, this proposed percentage of current Newfield stockholder ownership in the combined company equated to a proposed exchange ratio of 2.8490 Encana common shares for each share of Newfield common
stock, or an implied offer price of $28.23 per share of common stock of Newfield using the Encana closing share price on October 29, 2018. Mr. Suttles indicated that he would discuss that proposal with the Encana board.

Later on October 29, 2018, Mr. Suttles called Mr. Boothby and advised him that the Encana board was prepared to consider an all-stock transaction in which Newfields current stockholders would own, in the aggregate, 34% of the issued and outstanding Encana common shares following the closing of the proposed transaction, which would
equate to a proposed exchange ratio of 2.3946 Encana common shares for each share of Newfield common stock, or an implied offer price of $23.73 per share of Newfield common stock based on the Encana closing share price on October 29, 2018.
Mr. Boothby informed Mr. Suttles that ownership of 34% of the issued and outstanding Encana common shares following the closing of the proposed transaction would not be acceptable and instead proposed 37%, to which Mr. Suttles
responded with 35% of the issued and outstanding Encana common shares following the closing of the proposed transaction. Messrs. Boothby and Suttles again

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discussed the unique combination and significant benefits that this transaction presented, including leveraging Encanas multi-basin advantage, the potential synergies and free cash flow
generated by the combined company and how the combined assets would complement one another. Following additional discussions, Messrs. Boothby and Suttles agreed that, subject to the completion of due diligence and negotiation of a satisfactory
merger agreement, each was prepared to recommend to their respective boards an all-stock transaction in which Newfields current stockholders would own, in the aggregate, 36.5% of the issued and
outstanding Encana common shares following the closing of the proposed transaction, which would equate to a proposed exchange ratio of 2.6719 Encana common shares for each share of Newfield common stock, or an implied offer price of $26.48 per share
of Newfield common stock using the Encana closing share price on October 29, 2018. Mr. Suttles advised Mr. Boothby that he would speak further to his board and, following discussions with Mr. Boothby, Mr. Suttles attended
Encanas board dinner in Denver, Colorado and provided an update to the Encana board of his discussions with Mr. Boothby, including the proposed merger consideration.

On October 30, 2018, the Encana board held a meeting. At the meeting, Encanas Executive Vice-President & General Counsel
provided an overview to the board of its fiduciary duties as well as key terms of the draft merger agreement. Encanas management then presented the benefits and risks of the transaction and potential synergies, followed by a presentation by
each of Credit Suisse and TD Securities to the Encana board. Following the presentations, Encanas board discussed the merits of the transaction, including the valuation, that the transaction would be accretive to Encanas shareholders and
that the acquisition cost of entering into STACK/SCOOP was very competitive relative to other transactions in the play.

The Newfield
board also met on October 30, 2018 to discuss the current status of the proposed transaction with Encana, including the exchange ratio and termination fees. Certain members of Newfield management and representatives of Newfields outside
counsel were also in attendance.

On October 30-31, 2018, representatives of Encana, Paul Weiss,
Newfield and Kirkland held telephonic meetings to finalize the outstanding terms of the merger agreement and to address outstanding due diligence items.

On October 31, 2018, Messrs. Boothby and Suttles spoke by telephone regarding certain outstanding matters related to the merger
agreement. Later that day, Newfield and Encana settled the remaining outstanding terms with respect to the merger agreement, including fixing the exchange ratio at 2.6719 Encana common shares for each share of Newfield common stock (which would
result in Newfield stockholders owning approximately 36.5% of the Encana common shares immediately after the closing of the merger) and setting the termination fee equal to $150 million payable by Newfield or $300 million payable by Encana
in the event that the merger agreement is terminated under certain circumstances.

On October 31, 2018, the Encana board met to
discuss the proposed transaction, including the proposed final terms of the merger agreement that the parties had negotiated. At such meeting, Credit Suisse provided an updated presentation and then rendered its oral opinion to the Encana board
(which was subsequently confirmed in writing by delivery of Credit Suisses written opinion addressed to the Encana board dated the same date) as to the fairness, from a financial point of view, to Encana of the exchange ratio specified in the
merger agreement. TD Securities provided a presentation and then also rendered its oral opinion to the Encana board (which was subsequently confirmed in writing by delivery of TD Securities written opinion addressed to the Encana board dated
the same date) that, as of such date and based on and subject to the matters considered, the procedures followed, the assumptions made and various limitations of, and qualifications to, the review undertaken by TD Securities as set forth in its
written opinion, the exchange ratio was fair, from a financial point of view, to Encana. Following a discussion of these matters, the Encana board unanimously (i) determined that the merger agreement and transactions contemplated thereby,
including the merger and the share issuance, were in the best interests of Encana, (ii) approved the execution and delivery of the merger agreement, the performance by Encana of its covenants and agreements contained therein and the
consummation of the transactions contemplated by the merger agreement, (iii) directed that the merger agreement be submitted to Encana shareholders at a special meeting of shareholders to approve the share issuance and (iv) resolved to
recommend that Encana shareholders approve the share issuance contemplated by the merger agreement.

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On the evening of October 31, 2018, the Newfield board held a telephonic meeting with
representatives of its legal and financial advisors. At this time, Newfield management and Newfields outside counsel informed the Newfield board that the remaining matters in the merger agreement had been resolved in a manner consistent with
the prior days discussions. A representative of J.P. Morgan then delivered to the Newfield board J.P. Morgans oral opinion, subsequently confirmed in writing, that, as of such date and based upon and subject to the assumptions made
and limitations to be set forth in the opinion, the exchange ratio was fair, from a financial point of view, to the holders of such shares. Following additional discussion, the Newfield board (i) unanimously determined that the terms of the
merger agreement and the transactions contemplated thereby, including the merger, are advisable, fair to, and in the best interests of, Newfield and its stockholders, (ii) unanimously approved and declared advisable the merger agreement and the
transactions contemplated by the merger agreement, including the merger, (iii) unanimously approved the execution and delivery by Newfield of the merger agreement, the performance by Newfield of its covenants and agreements contained therein
and the consummation of the transactions contemplated by the merger agreement, including the merger, upon the terms and subject to the conditions contained therein, (iv) unanimously directed that the merger agreement be submitted to
Newfields stockholders at the Newfield special meeting to approve its adoption, (v) took all actions necessary so that the restrictions on business combinations and stockholder vote requirements contained in Section 203 of the DGCL
and any other applicable law with respect to a moratorium, control share acquisition, business combination, fair price or other forms of anti-takeover laws that may purport to be applicable will not
apply with respect to or as a result of the entry into the merger agreement and the consummation of the transactions contemplated thereby, including the merger, and (vi) unanimously resolved to recommend that the Newfield stockholders approve
the adoption of the merger agreement.

That evening, Kirkland and Paul Weiss finalized the terms of the merger agreement and ancillary
documents, following which Encana, Newfield and Merger Sub executed and delivered the merger agreement that same day.

Prior to the
opening of North American stock markets on November 1, 2018, Encana and Newfield issued a joint news release announcing the proposed combination and Encana hosted a conference call and webcast for the investment community to discuss the terms
of the merger.

Recommendation of the Encana Board and Reasons for the Merger

The Encana board unanimously determined the merger agreement and the transactions contemplated by the merger agreement, including the issuance
of Encana shares in connection with the merger, to be in the best interests of Encana and approved the merger agreement and the transactions contemplated by the merger agreement. The Encana board unanimously recommends that Encana
shareholders vote FOR the share issuance proposal and FOR the Encana adjournment proposal.

In evaluating the merger, the Encana board consulted with Encana management, as well as Encanas financial and legal advisors, and
considered a number of factors, weighing both the perceived benefits of the merger as well as potential risks of the merger.

In the
course of its deliberations, the Encana board considered a variety of factors and information that it believes support its determinations and recommendations, including the following factors:



the merger is expected to be immediately accretive to key elements of Encanas five-year plan, including non-GAAP cash flow per share and free cash flow and, as a result, it is expected that Encana will, following completion of the merger:



increase its regular dividend by 25%; and



expand its share buyback program from $400 million to $1.5 billion, with the remaining
$1.25 billion planned to be completed in 2019;

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in each case to be funded with expected
non-GAAP free cash flow and cash on hand;



the merger will create a leading multi-basin company with premium, liquids-weighted positions in three of North
Americas highest quality, lowest supply cost basins: the Permian, STACK/SCOOP and Montney;



this enhanced multi-basin portfolio is expected to continue Encanas competitive advantage to allow Encana
to manage risk, provide optionality to direct capital to its highest margin opportunities and transfer learnings across the business; and



the merger will increase oil and condensate production by over 54% and increase proved reserves by approximately
85%;



the acquisition of Newfield adds a significant premium position in the core of the world-class, oil-rich, STACK/SCOOP in the Anadarko Basin, a basin that Encanas technical team has studied since 2013 when Encana launched its strategy to become a leading North American resource company, allowing Encana to
unlock value because:



this premium, oil-weighted,stacked-pay asset contains multiple commercial and prospective zones that Encana believes are well suited to its proven cube development model;



this asset contains over 6,000 gross risked well locations and about 3 billion BOE of net unrisked resource;
and



this entry into the STACK/SCOOP in the Anadarko basin was attractive to Encana in comparison to other acquisition
opportunities reasonably available to Encana, as well as in comparison to previous transactions in the basin.



the merger is expected to create approximately $250 million of annual synergies through cube development,
operational efficiencies and overhead savings;



the combination of Encana and Newfields strong balance sheets are expected to create an even stronger
investment grade company, providing Encana with additional financial flexibility and resiliency through the commodity price cycles;



Encanas past record of successfully integrating acquisitions and realizing the projected financial goals
and benefits of acquisitions, and Encana managements belief that Encana will be able to extract significant value from Newfields assets;



Encana will continue to be led by its current strong, experienced management team, and that the addition of two
current Newfield directors to the Encana board post-merger will add further valuable expertise and experience and in-depth familiarity with Newfields assets to the Encana board, which will enhance the
likelihood of realizing the strategic benefits that Encana expects to derive from the merger;



Encana boards knowledge of, and discussions with Encana management and its advisors regarding,
Encanas and Newfields business operations, financial condition, earnings and prospects, taking into account Encanas due diligence investigation of Newfield;



the oral opinion of Credit Suisse rendered to the Encana board on October 31, 2018 (which was subsequently
confirmed in writing by delivery of Credit Suisses written opinion addressed to the Encana board dated the same date, which is included as Annex B) to the effect that as of the date of such opinion, and subject to the procedures followed,
assumptions made, qualifications and limitations on the review undertaken and other matters considered by Credit Suisse in preparing its opinion, the exchange ratio was fair from a financial point of view to Encana, as further described in the
section entitled Opinions of Encanas Financial Advisors  Opinion of Credit Suisse;



the oral opinion of TD Securities rendered to the Encana board on October 31, 2018 (which was subsequently
confirmed in writing by delivery of TD Securities written opinion addressed to the Encana board dated the same date, which is included as Annex C) to the effect that as of the date of

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such opinion, and based on and subject to the matters considered, the procedures followed, the assumptions made and various limitations of, and qualifications to, the review undertaken by TD
Securities as set forth in its written opinion, the exchange ratio was fair, from a financial point of view, to Encana, as further described in the section entitled Opinions of Encanas Financial Advisors  Opinion of TD
Securities;



the restrictions imposed on Encanas business and operations during the pendency of the merger are
reasonable and not unduly burdensome;



the exchange ratio is fixed and will not fluctuate in the event that the market price of Newfield common stock
increases relative to the market price of Encana common shares between the date of the merger agreement and the closing of the merger;



the likelihood of consummation of the merger and the Encana boards evaluation of the likely time frame
necessary to close the merger;



Encana shareholders will have the opportunity to vote on the share issuance proposal, which is a condition
precedent to the merger; and



the representations, warranties, covenants and conditions contained in the merger agreement, including the
following:



that Encana has the ability, in specified circumstances, to provide information to and to engage in discussions
or negotiations with a third party that makes an unsolicited acquisition proposal, as further described in the section entitled The Merger AgreementNo Solicitation of Alternative Proposals;



that the Encana board has the ability, in specified circumstances, to change its recommendation to Encana
shareholders to vote in favor of the share issuance proposal, as further described in the section entitled The Merger AgreementChange in Board Recommendation;



that there are limited circumstances in which the Newfield board may terminate the merger agreement or change its
recommendation that Newfield stockholders approve the merger agreement proposal, and if the merger agreement is terminated by Encana as a result of a change in recommendation of the Newfield board or by Newfield in order to enter into a definitive
agreement with a third party providing for the consummation of a superior proposal, then in each case Newfield has agreed to pay Encana a termination fee of $150 million, as further described in the section entitled The Merger
AgreementExpenses and Termination Fees Relating to the Termination of the Merger AgreementTermination Fees payable by Newfield; and



that if the merger agreement is terminated by either party because Newfield stockholders do not approve the
merger agreement proposal, then Newfield has agreed to pay Encana an expense reimbursement fee of $50 million, as further described in the section entitled The Merger Agreement Expenses and Termination Fees Relating to the
Termination of the Merger AgreementExpenses.

In the course of its deliberations, the Encana board also
considered a variety of risks, uncertainties and other potentially negative factors, including the following factors:



the merger may not be completed in a timely manner or at all and the potential consequences of non-completion or delays in completion;



the effect that the length of time from announcement until completion of the merger could have on the market
price of Encana common shares, Encanas operating results and the relationship with Encanas employees, shareholders, customers, suppliers, regulators and others who do business with Encana;



Encana will be entering into a new basin in which it has not previously operated, despite the fact that
Encanas technical team has studied the STACK/SCOOP for years;

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

that the integration of Encana and Newfield may not be as successful as expected and that the anticipated
benefits of the merger may not be realized in full or in part, including the risk that synergies may not be achieved or not achieved in the expected time frame;



Encanas senior management may be diverted from other priorities to implement the merger and make
arrangements for the integration of Encanas and Newfields operations, assets and employees following the merger;



Newfield stockholders may not approve the merger agreement proposal;



Encana shareholders may not approve the share issuance proposal;



the exchange ratio is fixed and will not fluctuate in the event that the market price of Encana common shares
increases relative to the market price of Newfield common stock between the date of the merger agreement and the closing of the merger;



the merger agreement imposes restrictions on Encanas ability to engage in certain business transactions,
which are described in the section entitled The Merger AgreementConduct of Business Conduct of Business by Encana and its Subsidiaries;



the merger agreement imposes restrictions on Encanas ability to solicit alternative proposals to the
merger, which is described in the section entitled The Merger Agreement No Solicitation of Alternative Proposals;



there are limited circumstances in which the Encana board may terminate the merger agreement or change its
recommendation that Encana shareholders approve the share issuance proposal, and if the merger agreement is terminated by Newfield as a result of a change in recommendation of the Encana board or by Encana in order to enter into a definitive
agreement with a third party providing for the consummation of a superior proposal, then Encana has agreed to pay Newfield a termination fee of $300 million, as further described in the section entitled The Merger AgreementExpenses
and Termination Fees Relating to the Termination of the Merger AgreementTermination Fees payable by Encana;



if the merger agreement is terminated by either party because Encana shareholders have not approved the share
issuance proposal, then Encana has agreed to pay Newfield an expense reimbursement fee of $50 million, as further described in the section entitled The Merger Agreement Expenses and Termination Fees Relating to the Termination of
the Merger AgreementExpenses;



the transaction costs to be incurred by Encana in connection with the merger;



the risks associated with the occurrence of events that may adversely affect the financial condition, properties,
assets, liabilities, business or results of operations of Newfield and its subsidiaries but that will not entitle Encana to terminate the merger agreement;



the potential impact on the market price of Encana common shares as a result of the issuance of the merger
consideration to Newfield stockholders; and



various other risks described in the section entitled Risk Factors beginning on page 39.

In determining to approve the merger agreement and the transactions contemplated by the merger agreement, the Encana
board took into account the factors set forth above, as well as others, and concluded that the potential benefits to Encana of the transactions contemplated by the merger agreement significantly outweighed the negative factors associated with the
transactions contemplated by the merger agreement.

The foregoing discussion of the information and factors considered by the Encana board
is not exhaustive. In view of the wide variety of factors considered by the Encana board in connection with its evaluation of the merger and the complexity of these matters, the Encana board did not consider it practical to, nor did it attempt to,
quantify, rank or otherwise assign relative weights to the specific factors that it considered in reaching its

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decision. In considering the factors described above and any other factors, individual members of the Encana board may have viewed factors differently or given different weight or merit to
different factors.

The foregoing discussion of the information and factors considered by the Encana board is forward-looking in nature
and should be read in light of the factors described in the section entitled Cautionary Statement Regarding Forward-Looking Statements beginning on page 36.

Recommendation of the Newfield Board and Reasons for the Merger

On October 31, 2018, the Newfield board unanimously determined that the terms of the merger agreement, the merger and the other
transactions contemplated by the merger agreement are advisable, fair to, and in the best interests of Newfield and its stockholders, and unanimously approved and declared advisable the merger agreement, the merger and the other transactions
contemplated by the merger agreement. The Newfield board unanimously recommends that Newfields stockholders vote FOR the merger agreement proposal, FOR the compensation proposal and FOR the Newfield
adjournment proposal.

In the course of reaching its recommendation, the Newfield board consulted with Newfields executive
management and its outside legal and financial advisors and considered several potentially positive factors, including the following (not necessarily presented in order of relative importance):



Benefits of a Combination with Encana.



Use of equity in the merger. It was deemed important by the Newfield board for stockholders to receive
Encana shares in an all-stock merger reflective of the relative value of the two companies. This would allow for Newfield stockholders to have a significant ownership position in a combined entity expected to
have free cash flow, production growth and the ability to immediately return capital to shareholders through dividends and share buybacks. In addition, the combined entity would have a superior capital structure, which would afford the ability to
develop a deep inventory of assets in North Americas premier Permian, STACK/SCOOP and Montney plays.



Exchange ratio. The exchange ratio of 2.6719 Encana common shares for each share of Newfield common stock
represents a premium of approximately 35% to the closing price of Newfields common stock on October 31, 2018, the last trading day before the public announcement of the merger. The all-stock merger
consideration will result in an increase in Newfield stockholders exposure to the potential upside of the combined company going forward, with Newfield stockholders being expected to own 36.5% of the combined company on a pro forma basis,
based on the number of shares of Newfield common stock and Encana common shares expected to be outstanding immediately prior to the consummation of the merger.



Multi-basin vs pure play business model; sustainability. The Newfield board believes that the multi-basin
business model for exploration and production companies and the unique size and the operational footprint of the combined company across multiple onshore liquids-focused resource plays reduces risks, allows for through-cycle development
of key plays and provides distinct advantages over the pure play, or single-basin, model. The combined company would benefit from the optionality provided from several large-scale positions in quality onshore resource plays. Capital investments
could be shifted between active drilling areas to react in a timely manner to changes in commodity prices, regulatory conditions, regional takeaway constraints and other factors.



Significant synergies. As the exploration and production industry is transitioning from resource capture
and play assessment to full-field development, the Newfield board considers consolidation to be an effective method of exploiting synergies and rapidly transferring key learnings across basins to improve returns. The elimination of duplicative
internal departments and positions, as well as an integration of the best and brightest personnel from both companies, is expected to provide additional benefits. The combined company is expected to compare favorably to all

77

onshore resource companies on a general and administrative expense per unit of production basis. Following a thorough analysis, the Newfield board determined that they were confident the
operational footprint, strong cost structure and balance sheet of the combined company, combined with Encanas cube development expertise, will enable the combined company to advance the development of Newfields assets for less capital
and realize the projected cost synergies. Encana subsequently disclosed estimated synergies of $250 million per year (50% related to operational synergies, primarily through well cost reductions in STACK/SCOOP, and 50% related to general and
administrative expenses).



Improved cost of capital. The merger is expected to be credit-enhancing. The size of the combined company
is expected to lead to a significantly lower cost of capital. When combined, the pro forma company will have net daily production of approximately 577,000 barrels of oil equivalent per day, proved reserves of more than 1.4 billion barrels of
oil equivalent and a deep inventory of drilling projects across multiple basins. The Newfield board believes that this will ultimately lead to improved credit ratings, lower cost of capital and improved access to capital markets through-cycle.



Portfolio optionality. The combined portfolios of the two companies will provide multiple options for the
optimization of non-strategic assets, if desired. Although the Newfield board did not have insights on any planned future actions, it believed that potential optimization activities could make funds available for other uses.



Corporate Governance. Newfields stockholders will have a continuing influence in the execution of
the strategy and business plan of the combined company through the appointment of two Newfield directors to the Encana board of directors in connection with the consummation of the merger.



Alternative Transactions.



The Newfield board believes, after thorough review of, and based on its knowledge of, Newfields strategic
goals and opportunities, and trends in and the competitive environment of the exploration and production industry, including the potential impact of those factors on the trading price of Newfield common stock (which cannot be precisely quantified
numerically), that the value offered to Newfields stockholders pursuant to the merger is more favorable to Newfields stockholders than the potential value that might reasonably be expected to result from remaining an independent public
company.



The Newfield board also considered alternative strategic transactions, including both acquiring and being
acquired by another public company, and, following review of such alternatives and consultation with Newfield management and its financial advisors, believed that it was unlikely an alternative strategic counterparty could consummate a transaction
that would be on superior terms and that would provide Newfield stockholders greater merger consideration than is being provided in connection with the merger.



Receipt of Fairness Opinion from J.P. Morgan. The Newfield board considered the financial analysis
reviewed and discussed with representatives of J.P. Morgan, as well as the oral opinion of J.P. Morgan rendered to the Newfield board, which was subsequently confirmed by delivery of a written opinion dated October 31, 2018, to the effect that,
as of such date, the exchange ratio was fair, from a financial point of view, to the holders of Newfield common stock. See the section entitled Opinion of Newfields Financial Advisor beginning on page 106.



Likelihood of Completion. The Newfield board considered the likelihood of completion of the merger to be
significant, in light of, among other things the belief that, in consultation with Newfields legal advisors, the terms of the merger agreement, taken as a whole, including the parties representations, warranties, covenants and conditions
to closing, and the circumstances under which the merger agreement may be terminated, are reasonable.

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

Opportunity to Receive Alternative Acquisition Proposals and to Terminate the Transaction in Order to Accept a
Superior Proposal. The Newfield board considered the terms of the merger agreement relating to Newfields ability to respond to unsolicited acquisition proposals, and the other terms of the merger agreement, including:



the fact that Newfield has the right, subject to certain conditions, to provide
non-public information in response to, and to discuss and negotiate, certain unsolicited acquisition proposals made before Newfields stockholders approve of the transaction (see the section entitled
The Merger AgreementNo Solicitation of Alternative Proposals beginning on page 145);



the provision of the merger agreement allowing the Newfield board, prior to obtaining Newfield stockholder
approval, to change its recommendation to Newfield stockholders with respect to the adoption of the merger agreement or to terminate the merger agreement to accept a superior proposal if it determines in good faith, after consultation with its
outside legal counsel and financial advisors, that the failure to take such action would reasonably be expected to be inconsistent with the Newfield boards fiduciary duties;



the belief of the Newfield board that the termination fee of $150 million, which may be payable by Newfield
in certain circumstances, is reasonable under the circumstances given the size of the transaction and taking into account the range of such termination fees in similar transactions (see the section entitled The Merger
AgreementTermination of the Merger Agreement and The Merger AgreementExpenses and Termination Fees Relating to the Termination of the Merger Agreement beginning on page 153);



that there are limited circumstances in which the Encana board may terminate the merger agreement or change its
recommendation that Encana shareholders approve the share issuance proposal, and if the merger agreement is terminated by Newfield as a result of a change in recommendation of the Encana board or by Encana in order to enter into a definitive
agreement with a third party providing for the consummation of a superior proposal, then in each case Encana has agreed to pay Newfield a termination fee of $300 million, as further described in the section entitled The Merger
AgreementExpenses and Termination Fees Relating to the Termination of the Merger AgreementTermination Fees payable by Encana; and



that if the merger agreement is terminated by either party because Encana shareholders do not approve the share
issuance proposal, then Encana has agreed to pay Newfield an expense reimbursement fee of $50 million, as further described in the section entitled The Merger AgreementExpenses and Termination Fees Relating to the Termination of the
Merger AgreementExpenses.

The Newfield board also considered and balanced against the potentially positive
factors a number of uncertainties, risks and other countervailing factors in its deliberations concerning the transaction and the other transactions contemplated by the merger agreement, including the following (not necessarily in order of relative
importance):



the fact that the exchange ratio in the merger agreement provides for a fixed number of Encana common shares,
and, as such, Newfield stockholders cannot be certain at the time of the Newfield special meeting of the market value of the merger consideration they will receive, and the possibility that Newfield stockholders could be adversely affected by a
decrease in the trading price of Encana common shares before the closing of the merger;



the fact that the market price of Newfield common stock could be affected by many factors, including: (i) if
the merger agreement is terminated, the reason or reasons for such termination and whether such termination resulted from factors adversely affecting Newfield; (ii) the possibility that, as a result of the termination of the merger agreement,
possible acquirers may consider Newfield to be an unattractive acquisition candidate; and (iii) the possible sale of Newfield common stock by short-term investors following an announcement that the merger agreement was terminated.

79



the fact that, under specified circumstances, Newfield may be required to pay certain termination fees in the
event the merger agreement is terminated and the effect this could have on Newfield, including:



the possibility that the $150 million termination fee payable by Newfield to Encana upon the termination of
the merger agreement in order to allow Newfield to enter into an agreement with respect to a superior proposal could discourage other potential acquirers from making a competing proposal, although the Newfield board believes that the termination fee
is reasonable in amount and will not unduly deter, preclude or restrict any other party that might be interested in acquiring Newfield; and



if the transaction is not consummated, Newfield will generally be required to pay its own expenses associated
with the transaction and, if the merger agreement is terminated for the failure of Newfields stockholders to approve the merger agreement and transactions contemplated thereby, Newfield will be required to pay Encana $50 million for
Encanas costs, fees and expenses incurred in connection with the transactions contemplated by the merger agreement;



the fact that the restrictions in the merger agreement on Newfields ability to actively solicit competing
bids to acquire it and to entertain other acquisition proposals unless certain conditions are satisfied;



the fact that the restrictions on Newfields conduct of business prior to completion of the transaction
could delay or prevent Newfield from undertaking business opportunities that may arise or taking other actions with respect to its operations during the pendency of the transaction;



the fact that the amount of time that may be required to consummate the transaction, including the fact that the
completion of the transaction depends on factors outside of Newfields or Encanas control and the risk that the pendency of the transaction for an extended period of time could have an adverse effect on Newfield;



the fact that the significant costs involved in connection with entering into the merger agreement and completing
the transaction and the substantial time and effort of management required to consummate the transaction could disrupt Newfields business operations;



the fact that the exchange of Newfield common stock for Encana common shares in the merger will be a taxable
transaction to the holders of Newfield common stock for U.S. federal income tax purposes (as more fully described in the section entitled Material U.S. Federal Income Tax Consequences of the Merger beginning on page 122); and



the risks and uncertainties associated with executing on Newfields business strategy and achieving
Newfields related financial projections and opportunities, including as described in the risk factors and forward looking information sections of Newfields disclosures filed with the SEC and in the sections
entitled Risk Factors and Cautionary Statement Regarding Forward-Looking Statements of this joint proxy statement/prospectus.

After taking into account the factors set forth above, as well as others, the Newfield board concluded that the risks, uncertainties,
restrictions and potentially negative factors associated with the transaction were outweighed by the potential benefits of the transaction to Newfields stockholders.

The foregoing discussion of factors considered by Newfield is not intended to be exhaustive, but summarizes the material factors considered by
the Newfield board. In light of the variety of factors considered in connection with their evaluation of the merger agreement and the transaction, Newfield did not find it practicable to, and did not, quantify, rank or otherwise assign relative
weights to the specific factors considered in reaching their determinations and recommendations. Moreover, each member of the Newfield board applied his or her own personal business judgment to the process and may have given different weight to
different factors. The Newfield board based its recommendation on the totality of the information presented, including thorough discussions with, and questioning of, Newfields executive management and the Newfield boards financial
advisors and outside legal counsel.

In considering the recommendation of the Newfield board to approve the merger agreement proposal,
Newfield stockholders should be aware that the executive officers and directors of Newfield have certain interests in the transaction that may be different from, or in addition to, the interests of Newfield stockholders

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generally. The Newfield board was aware of these interests and considered them when approving the merger agreement and recommending that Newfield stockholders vote to approve the merger agreement
proposal. See the section entitled Interests of Certain Newfield Directors and Executive Officers in the Merger beginning on page 115.

It should be noted that this explanation of the reasoning of the Newfield board and certain information presented in this section is
forward-looking in nature and should be read in light of the factors set forth in Cautionary Statement Concerning Forward-Looking Statements beginning on page 36.

Encana does not as a matter of course make public long-term forecasts or internal projections as to future performance, revenues, production,
earnings or other results due to, among other reasons, the uncertainty of the underlying assumptions and estimates. However, Encanas management authorized the use of and reliance upon certain unaudited internal financial forecasts by Credit
Suisse and TD Securities in connection with their respective financial analyses and opinions described in the section entitled Opinions of Encanas Financial Advisors, which forecasts were provided to the Encana board in connection
with its evaluation of the proposed merger. The inclusion of this information should not be regarded as an indication that any of Encana, Newfield, their respective advisors or other representatives or any other recipient of this information
considered, or now considers, it to be necessarily predictive of actual future performance or events, or that it should be construed as financial guidance, and such summary projections set forth below should not be relied on as such.

This information was prepared solely for internal use and is subjective in many respects. While presented with numeric specificity, the
unaudited prospective financial and operating information reflects numerous estimates and assumptions that are inherently uncertain and may be beyond the control of Encanas management, including, among others, Encanas and Newfields
future results, oil and gas industry activity, commodity prices, demand for natural gas and crude oil, the availability of financing to fund the exploration and development costs associated with the respective projected drilling programs, general
economic and regulatory conditions and other matters described in the sections entitled Cautionary Statement Regarding Forward-Looking Statements and Risk Factors. The unaudited prospective financial and operating information
reflects both assumptions as to certain business decisions that are subject to change and, in many respects, subjective judgment, and thus is susceptible to multiple interpretations and periodic revisions based on actual experience and business
developments. Encana and Newfield can give no assurance that the unaudited prospective financial and operating information and the underlying estimates and assumptions will be realized. In addition, since the unaudited prospective financial and
operating information is prepared at a point in time, inherently forward-looking and covers multiple years, such information by its nature may not be predictive of successive years. Actual results may differ materially from those set forth below,
and important factors that may affect actual results and cause the unaudited prospective financial information to be inaccurate include, but are not limited to, risks and uncertainties relating to Encanas business, industry performance, the
regulatory environment, general business and economic conditions and other matters described under the section of this joint proxy statement/prospectus entitled Risk Factors. See also Cautionary Statement Regarding Forward-Looking
Statements and Where You Can Find More Information.

The unaudited prospective financial and operating information was
not prepared with a view toward public disclosure, nor was it prepared with a view toward compliance with GAAP, published guidelines of the SEC or the guidelines established by the American Institute of Certified Public Accountants for preparation
and presentation of prospective financial information. Neither Encanas independent registered public accounting firm, nor any other independent accountants, have compiled, examined or performed any procedures with respect to the unaudited
prospective financial and operating information contained herein, nor have they expressed any opinion or any other form of assurance on such information or its achievability. The report of the independent registered public accounting firm to Encana
contained in its Annual Report on Form 10-K for the year ended December 31, 2017, which is incorporated by reference into this joint proxy statement/prospectus, relates to historical financial information
of Encana, and such report does not extend to the projections included below and should not be read to do so.

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Furthermore, the unaudited prospective financial and operating information does not take
into account any circumstances or events occurring after the date it was prepared. Encana and Newfield can give no assurance that, had the unaudited prospective financial and operating information been prepared either as of the date of the merger
agreement or as of the date of this joint proxy statement/prospectus, similar estimates and assumptions would be used. Except as required by applicable securities laws, Encana and Newfield do not intend to, and disclaim any obligation to, make
publicly available any update or other revision to the unaudited prospective financial and operating information to reflect circumstances existing since their preparation or to reflect the occurrence of unanticipated events, even in the event that
any or all of the underlying assumptions are shown to be in error, including with respect to the accounting treatment of the merger under GAAP, or to reflect changes in general economic or industry conditions. The unaudited prospective financial and
operating information does not take into account all the possible financial and other effects on Encana or Newfield of the merger, the effect on Encana or Newfield of any business or strategic decision or action that has been or will be taken as a
result of the merger agreement having been executed, or the effect of any business or strategic decisions or actions which would likely have been taken if the merger agreement had not been executed, but which were instead altered, accelerated,
postponed or not taken in anticipation of the merger. Further, the unaudited prospective financial and operating information does not take into account the effect on Encana or Newfield of any possible failure of the merger to occur. None of Encana,
Newfield, or their respective affiliates, officers, directors, advisors or other representatives has made, makes or is authorized in the future to make any representation to any Encana shareholder or Newfield stockholder or other person regarding
Encanas or Newfields ultimate performance compared to the information contained in the unaudited prospective financial and operating information or that the forecasted results will be achieved. The inclusion of the unaudited prospective
financial and operating information herein should not be deemed an admission or representation by Encana, Newfield, their respective advisors or any other person that it is viewed as material information of Encana or Newfield, particularly in light
of the inherent risks and uncertainties associated with such forecasts. The summary of the unaudited prospective financial and operating information included below is not being included to influence your decision whether to vote in favor of the
merger agreement proposal, the share issuance proposal or any other proposal to be considered at the special meetings, but is being provided solely because it was authorized by Encanas management to be used and relied upon by Credit Suisse and
TD Securities in connection with their respective financial analyses and opinions described in the section entitled Opinions of Encanas Financial Advisors, which forecasts were provided to the Encana board in connection with its
evaluation of the proposed merger.

In light of the foregoing, and considering that the special meetings will be held several months after
the unaudited prospective financial and operating information was prepared, as well as the uncertainties inherent in any forecasted information, Encana shareholders and Newfield stockholders are cautioned not to place undue reliance on such
information, and Encana and Newfield urge all Encana shareholders and Newfield stockholders to review Encanas most recent SEC filings for a description of Encanas reported financial results and Newfields most recent SEC filings for
a description of Newfields reported financial results. See the section entitled Where You Can Find More Information.

In preparing the prospective financial and operating
information for Encana described below, Encanas management authorized the use of the following price assumptions, which are based on (1) NYMEX oil and gas strip pricing available as of approximately 5:45 p.m. (EST) on October 30,
2018 and (2) Wall Street consensus pricing with respect to future commodity prices for oil and natural gas, per Bloomberg, as of October 30, 2018:

NYMEX oil and gas strip pricing

2019E

2020E

2021E

2022E

Oil price ($/Bbl)

$

66.68

$

64.60

$

61.98

$

59.50

Gas price ($/Mmbtu)

$

2.83

$

2.67

$

2.60

$

2.61

Wall Street consensus pricing

2019E

2020E

2021E

2022E

Oil price ($/Bbl)

$

69.25

$

66.13

$

63.50

$

63.50

Gas price ($/Mmbtu)

$

2.99

$

3.01

$

3.05

$

3.05

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The following tables present selected unaudited prospective financial and operating
information, on an unrisked basis, for certain assets of Encana for the fiscal years ending 2019 through 2022, based on the above (1) NYMEX oil and gas strip pricing available as of approximately 5:45 p.m. (EST) on October 30, 2018 and
(2) Wall Street consensus pricing, per Bloomberg, as of October 30, 2018 (in millions, other than production data), and that were authorized by Encanas management to be used and relied upon by Credit Suisse and TD Securities in
connection with their respective financial analyses and opinions described in the section entitled Opinions of Encanas Financial Advisors. Certain adjustments were made to the unaudited prospective financial and operating
information of Encana in connection with the financial analyses performed by TD Securities at the direction or authorization of the management of Encana. The following selected unaudited prospective financial and operating information should not
be regarded as an indication that Encana considered, or now considers, it to be necessarily predictive of actual future performance or events, or that it should be construed as financial guidance, and such information does not take into account
any circumstances or events occurring after thedate it was prepared, including, among other things, Encanas anticipated or actual capital allocation relating to the Encana assets post-closing of the merger.

Represents Daily Production, EBITDA and Unlevered Free Cash Flow from certain assets of Encana and may not be
representative of Encanas total consolidated Daily Production, EBITDA and Unlevered Free Cash Flow.

(2)

EBITDA is defined as earnings before interest, taxes, depreciation and amortization. EBITDA is a non-GAAP measure and has no standardized meaning under GAAP. This measure should not be considered as an alternative to net earnings or other measures derived in accordance with GAAP.

(3)

Unlevered Free Cash Flow is defined as EBITDA adjusted for the cash flow impact of cash taxes and capital
expenditures. Unlevered Free Cash Flow does not include any estimated synergies. Unlevered Free Cash Flow is a non-GAAP measure and has no standardized meaning under GAAP. This measure should not be considered
as an alternative to net earnings or other measures derived in accordance with GAAP.

Encanas management also authorized the use of and reliance upon certain unaudited prospective financial and operating information with
respect to Newfield, which was generally derived from publicly available information related to Newfield as well as the unrisked information provided by Newfields management and summarized in this joint proxy statement/prospectus under the
caption Certain Newfield Unaudited Prospective Financial and Operating Information, by Credit Suisse and TD Securities in connection with their respective financial analyses and opinions described in the section entitled
Opinions of Encanas Financial Advisors, which forecasts were provided to the Encana board in connection with its evaluation of the proposed merger.

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The following tables present selected unaudited prospective financial and operating
information, on an unrisked basis, for Newfield for the fiscal years ending 2019 through 2022, based on the above (1) NYMEX oil and gas strip pricing available as of approximately 5:45 p.m. (EST) on October 30, 2018 and (2) Wall
Street consensus pricing, per Bloomberg, as of October 30, 2018 (in millions, other than production data), and that were authorized by Encana to be used and relied upon by Credit Suisse and TD Securities in connection with their respective
financial analyses and opinions described in the section entitled Opinions of Encanas Financial Advisors. Certain adjustments were made to the unaudited prospective financial and operating information of Newfield in connection with
the financial analyses performed by TD Securities at the direction or authorization of the management of Encana. The following selected unaudited prospective financial and operating information should not be regarded as an indication that Encana
considered, or now considers, it to be necessarily predictive of actual future performance or events, or that it should be construed as financial guidance, and such information does not take into account any circumstances or events occurring after
the date it wasprepared, including, among other things, Encanas anticipated or actual capital allocation relating to the Newfield assets post-closing of the merger.

EBITDA is defined as earnings before interest, taxes, depreciation and amortization. EBITDA is a non-GAAP measure and has no standardized meaning under GAAP. This measure should not be considered as an alternative to net earnings or other measures derived in accordance with GAAP.

(2)

Unlevered Free Cash Flow is defined as EBITDA adjusted for the cash flow impact of cash taxes and capital
expenditures. Unlevered Free Cash Flow does not include any estimated synergies. Unlevered Free Cash Flow is a non-GAAP measure and has no standardized meaning under GAAP. This measure should not be considered
as an alternative to net earnings or other measures derived in accordance with GAAP.

In addition, Encanas
management provided to the Encana board and Encanas financial advisors certain estimates of the amounts and timing of cost savings, net of costs necessary to achieve such cost savings, anticipated by Encanas management to result from the
merger, which consisted of estimated annual run rate cost savings of between $180$250 million, with incremental costs of up to approximately $150 million to achieve such cost savings (such estimated annual net cost savings, the
Expected Synergies). The Expected Synergies also were provided to each of Credit Suisse and TD Securities for use and reliance in connection with their respective opinions and related financial analyses described in the section entitled
Opinions of Encanas Financial Advisors.

Newfield does not as a matter of course make public long-term forecasts or internal projections as to future performance,
revenues, production, earnings or other results due to, among other reasons, the uncertainty of the underlying assumptions and estimates. However, in connection with its evaluation of the merger, Newfields management prepared certain unaudited
internal financial forecasts with respect to Newfield, which were

84

provided to the Newfield board in connection with their evaluation of the proposed merger. Such forecasts were also provided to J.P. Morgan for its use and reliance in connection with its
financial analysis and opinion described in the section entitled  Opinion of Newfields Financial Advisor. The inclusion of this information should not be regarded as influential on your decision whether to vote for or against
the merger proposal or as an indication that any of Newfield, Encana, their respective advisors or other representatives or any other recipient of this information considered, or now considers, it to be necessarily predictive of actual future
performance or events, or that it should be construed as financial guidance, and such summary projections set forth below should not be relied on as such.

This information was prepared solely for internal use and is subjective in many respects. While presented with numeric specificity, the
unaudited prospective financial and operating information reflects numerous estimates and assumptions that were deemed to be reasonable as of the respective dates, but are inherently uncertain and may be beyond the control of Newfields
management. These assumptions include, but are not limited to Newfields and Encanas future results, oil and gas industry activity, commodity prices, demand for natural gas and crude oil, the availability of financing to fund the
exploration and development costs associated with the respective projected drilling programs, general economic and regulatory conditions and other matters described in the sections entitled Cautionary Statement Regarding Forward-Looking
Statements and Risk Factors. The unaudited prospective financial and operating information reflects both assumptions as to certain business decisions that are subject to change and, in many respects, subjective judgment, and thus
is susceptible to multiple interpretations and periodic revisions based on actual experience and business developments. Newfield and Encana can give no assurance that the unaudited prospective financial and operating information and the underlying
estimates and assumptions will be realized.

In addition, since the unaudited prospective financial and operating information is
inherently forward looking and covers multiple years, such information by its nature becomes less predictive with each successive year. Actual results may differ materially from those set forth below, and important factors that may affect actual
results and cause the unaudited prospective financial information to be inaccurate include, but are not limited to, risks and uncertainties relating to Newfields business, industry performance, the regulatory environment, general business and
economic conditions and other matters described under the section of this joint proxy statement/prospectus entitled Risk Factors. See also Cautionary Statement Regarding Forward-Looking Statements and Where You Can Find
More Information.

The unaudited prospective financial and operating information was not prepared with a view toward public
disclosure, nor was it prepared with a view toward compliance with GAAP, published guidelines of the SEC or the guidelines established by the American Institute of Certified Public Accountants for preparation and presentation of prospective
financial information. Neither Newfields independent registered public accounting firm, nor any other independent accountants, have compiled, examined or performed any procedures with respect to the unaudited prospective financial and
operating information contained herein, nor have they expressed any opinion or any other form of assurance on such information or its achievability. The report of the independent registered public accounting firm to Newfield contained in its Annual
Report on Form 10-K for the year ended December 31, 2017, which is incorporated by reference into this joint proxy statement/prospectus, relates to historical financial information of Newfield, and such
report does not extend to the projections included below and should not be read to do so. The unaudited prospective financial and operating information set forth in this section of this joint proxy statement/prospectus entitled Certain
Newfield Unaudited Prospective Financial and Operating Information has been prepared by, and is the responsibility of, Newfields management.

Furthermore, the unaudited prospective financial and operating information does not take into account any circumstances or events occurring
after the date it was prepared. Newfield and Encana can give no assurance that, had the unaudited prospective financial and operating information been prepared either as of the date of the merger agreement or as of the date of this joint proxy
statement/prospectus, similar estimates and assumptions would be used. Except as required by applicable securities laws, Newfield and Encana do not intend to, and disclaim any obligation to, make publicly available any update or other revision to
the unaudited prospective financial and operating information to reflect circumstances existing since their preparation or to reflect the occurrence of unanticipated events, even in the event that any or all of the underlying assumptions are shown
to

85

be in error, including with respect to the accounting treatment of the merger under GAAP, or to reflect changes in general economic or industry conditions.

The unaudited prospective financial and operating information does not take into account all the possible financial and other effects on
Newfield or Encana of the merger, the effect on Newfield or Encana of any business or strategic decision or action that has been or will be taken as a result of the merger agreement having been executed, or the effect of any business or strategic
decisions or actions which would likely have been taken if the merger agreement had not been executed, but which were instead altered, accelerated, postponed or not taken in anticipation of the merger. Further, the unaudited prospective financial
and operating information does not take into account the effect on Newfield or Encana of any possible failure of the merger to occur. None of Encana, Newfield, or their respective affiliates, officers, directors, advisors or other representatives
has made, makes or is authorized in the future to make any representation to any Newfield stockholder or Encana shareholder or other person regarding Newfields or Encanas ultimate performance compared to the information contained in the
unaudited prospective financial and operating information or that the forecasted results will be achieved. The inclusion of the unaudited prospective financial and operating information herein should not be deemed an admission or representation by
Newfield, Encana, their respective advisors or any other person that it is viewed as material information of Newfield or Encana, particularly in light of the inherent risks and uncertainties associated with such forecasts. The summary of the
unaudited prospective financial and operating information included below is not being included to influence your decision whether to vote in favor of the merger agreement proposal or any other proposal to be considered at the special meetings, but
is being provided solely because it was made available to the Newfield board and Newfields financial advisor in connection with the merger.

In light of the foregoing, and considering that the special meetings will be held several months after the unaudited prospective financial and
operating information was prepared, as well as the uncertainties inherent in any forecasted information, Newfield stockholders and Encana shareholders are cautioned not to place undue reliance on such information, and Newfield and Encana urge all
Newfield stockholders and Encana shareholders to review Newfields most recent SEC filings for a description of Newfields reported financial results and Encanas most recent SEC filings for a description of Encanas reported
financial results. See the section entitled Where You Can Find More Information.

In preparing the prospective financial and operating information for Newfield described below,
the management team of Newfield used the following price assumptions, which are based on (1) NYMEX oil and gas strip pricing and (2) Wall Street consensus pricing with respect to future commodity prices for oil and natural gas, in each
case, as of October 30, 2018:

NYMEX oil and gas strip pricing

4Q2018E

2019E

2020E

2021E

2022E

Oil price ($/Bbl)

$

69.05

$

66.51

$

64.57

$

61.93

$

59.49

Gas price ($/Mmbtu)

$

3.19

$

2.81

$

2.66

$

2.60

$

2.61

Wall Street consensus pricing

4Q2018E

2019E

2020E

2021E

2022E

Oil price ($/Bbl)

$

68.82

$

66.86

$

65.44

$

64.56

$

64.56

Gas price ($/Mmbtu)

$

2.89

$

2.84

$

2.94

$

2.92

$

2.92

The following table presents selected unaudited forecasted financial data, on a risked basis, for Newfield for
the fourth quarter of 2018 and the fiscal years ending 2019 through 2022 provided to the Newfield board and

86

Newfields financial advisor based on the above NYMEX oil and gas strip pricing as of October 30, 2018 (in millions, other than production data).

The following table presents selected unaudited forecasted financial data, on a risked basis, for Newfield for
the fourth quarter of 2018 and fiscal years ending 2019 through 2022 provided to the Newfield board and Newfields financial advisor based on the above Wall Street consensus pricing as of October 30, 2018 (in millions, other than
production data).

EBITDAX is defined as earnings before interest, taxes, depreciation, amortization and exploration expenses.
EBITDAX is a non-GAAP measure and has no standardized meaning under GAAP. This measure should not be considered as an alternative to net earnings or other measures derived in accordance with GAAP.

(2)

Operating Cash Flow is defined as EBITDAX less cash interest expense and cash taxes. Operating Cash Flow is a non-GAAP measure and has no standardized meaning under GAAP. This measure should not be considered as an alternative to other measures derived in accordance with GAAP.

Newfields management directed J.P. Morgan to rely for purposes of J.P. Morgans analysis upon the risked forecasts reflecting
parameters on select assumptions because Newfields management regarded such risked forecasts as more reasonable and achievable than un-risked forecasts; the
un-risked Newfield forecasts were not relied upon or taken into account in J.P. Morgans analysis.

Newfield Management Projections for Encana

Newfield management also provided to the Newfield board and to J.P. Morgan for its use and reliance in connection with its financial analysis
and opinion certain unaudited prospective financial and operating information with respect to Encana, which was generally derived from publicly available information related to Encana as well as the information provided by Encana management and
summarized in this joint proxy statement/prospectus under the caption Certain Encana Unaudited Prospective Financial and Operating Information, except that Newfield management adjusted the information provided by Encana management
in order to harmonize certain of the assumptions underlying such information with the assumptions underlying Newfields prospective financial information summarized above.

87

The following tables set forth a summary of this adjusted prospective financial and
operating information regarding Encana, as prepared by Newfield management, for the fourth quarter of 2018 and fiscal years ending 2019 through 2022 based on the above NYMEX oil and gas strip pricing and Wall Street consensus pricing as of
October 30, 2018 (in millions, other than production data).

EBITDAX is defined as earnings before interest, taxes, depreciation, amortization and exploration expenses.
EBITDAX is a non-GAAP measure and has no standardized meaning under GAAP. This measure should not be considered as an alternative to net earnings or other measures derived in accordance with GAAP.

(2)

Operating Cash Flow is defined as EBITDAX less cash interest expense and cash taxes. Operating Cash Flow is a non-GAAP measure and has no standardized meaning under GAAP. This measure should not be considered as an alternative to other measures derived in accordance with GAAP.

Opinions of Encanas Financial Advisors

Opinion of Credit Suisse

On
October 31, 2018, Credit Suisse rendered its oral opinion to the Encana board (which was subsequently confirmed in writing by delivery of Credit Suisses written opinion addressed to the Encana board dated the same date) as to, as of
October 31, 2018, the fairness, from a financial point of view, to Encana of the exchange ratio in the merger pursuant to the merger agreement.

Credit Suisses opinion was directed to the Encana board (in its capacity as such), and only addressed the fairness, from a financial
point of view, to Encana of the exchange ratio in the merger pursuant to the merger agreement and did not address any other aspect or implication (financial or otherwise) of the merger. The summary of Credit Suisses opinion in this joint proxy
statement/prospectus is qualified in its entirety by reference to the full text of its written opinion, which is included as Annex B to this joint proxy statement/prospectus and sets forth the procedures followed, assumptions made, qualifications
and limitations on the review undertaken and other matters considered by Credit Suisse in preparing its opinion. However, neither Credit Suisses written opinion nor the summary of its opinion and the related analyses set forth in this joint
proxy statement/prospectus are intended to be, and they do not constitute, advice or a recommendation to any securityholder as to how such holder should vote or act on any matter relating to the merger.

In arriving at its opinion, Credit Suisse:



reviewed a draft dated October 31, 2018 of the merger agreement and certain publicly available business and
financial information relating to Newfield and Encana;

88



reviewed certain other information relating to Newfield and Encana, including:



financial forecasts and projected production and operating data prepared or otherwise authorized by Encana
management for use and reliance by Credit Suisse relating to Newfield (the Encana Projections for Newfield), which were based on certain oil and gas reserve information prepared by Newfields management regarding its oil and gas
reserves (the Newfield Reserve Information);



financial forecasts and projected production and operating data, as well as an estimate of the value of certain
acreage not accounted for in the projected production and operating data, prepared or otherwise authorized by Encana management for use and reliance by Credit Suisse relating to Encana (the Encana Projections for Encana), which were
based on certain oil and gas reserve information prepared by Encanas management regarding its oil and gas reserves (the Encana Reserve Information);



riskings for Newfields oil and gas reserves prepared or otherwise authorized by Encana management for use
and reliance by Credit Suisse (the Encana Riskings for Newfield);



riskings for Encanas oil and gas reserves authorized by Encana management for use and reliance by Credit
Suisse (the Encana Riskings for Encana); and

reviewed estimates prepared and provided to Credit Suisse by Encanas management with respect to the cost
savings, net of costs necessary to achieve such cost savings, anticipated by such management to result from the merger;



spoke with the managements of Newfield and Encana and certain of their respective representatives regarding the
business and prospects of Newfield and Encana, and Newfields and Encanas respective oil and gas reserves and their respective oil and gas development and operating assumptions;



considered certain financial and stock market data of Newfield and Encana, and compared that data with similar
data for other companies with publicly traded equity securities in businesses that Credit Suisse deemed similar to those of Newfield and Encana, respectively;



considered, to the extent publicly available, the financial terms of certain other business combinations and
other transactions that had been effected or announced; and



considered such other information, financial studies, analyses and investigations and financial, economic and
market criteria that Credit Suisse deemed relevant.

In connection with its review, Credit Suisse did not independently
verify any of the foregoing information, and Credit Suisse assumed that such information was complete and accurate in all respects material to its analyses and opinion and relied upon such assumption. With respect to the Encana Projections for
Newfield that Credit Suisse used in its analyses, management of Encana advised Credit Suisse, and Credit Suisse assumed, that those financial forecasts were reasonably prepared in good faith and reflected such managements best currently
available estimates and judgments as to the future financial performance of Newfield. With respect to the Encana Projections for Encana (and other estimates of Encanas management described above) that Credit Suisse used in its analyses,
management of Encana advised Credit Suisse, and Credit Suisse assumed, that those financial forecasts and other estimates were reasonably prepared in good faith and reflected such managements best currently available estimates and judgments as
to the future financial performance of Encana and the other matters addressed thereby. With respect to the Newfield Reserve Information that Credit Suisse reviewed, management of Newfield advised Credit Suisse, and Credit Suisse assumed, that such
reserve information was reasonably prepared in good faith and reflected such managements best currently available estimates and

89

judgments as to Newfields oil and gas reserves. With respect to the Encana Reserve Information that Credit Suisse reviewed, management of Encana advised Credit Suisse, and Credit Suisse
assumed, that such reserve information was reasonably prepared in good faith and reflected such managements best currently available estimates and judgments as to Encanas oil and gas reserves. With respect to the Encana Riskings for
Newfield and the Encana Riskings for Encana, management of Encana advised Credit Suisse, and Credit Suisse assumed, that such riskings were reasonably prepared in good faith and reflected such managements best currently available estimates and
judgments as to the appropriate riskings for the Newfield Reserve Information and the Encana Reserve Information, respectively.

Credit
Suisse expressed no view or opinion with respect to the Encana Projections for Newfield, the Encana Projections for Encana, the Newfield Reserve Information, the Encana Reserve Information, the Encana Riskings for Newfield, the Encana Riskings for
Encana, the Future Pricing Data, or the assumptions upon which any of the foregoing were based. At Encanas direction, Credit Suisse assumed that the Encana Projections for Newfield, the Encana Projections for Encana, the Newfield Reserve
Information, the Encana Reserve Information, the Encana Riskings for Newfield, the Encana Riskings for Encana and the Future Pricing Data, taken together, were a reasonable basis on which to evaluate Newfield, Encana and the merger, and Credit
Suisse used and relied upon such information for purposes of its analyses and opinion.

In addition, Credit Suisse relied upon, without
independent verification (i) the assessments of the management of Encana with respect to Encanas ability to integrate the businesses of Newfield and Encana and (ii) the assessments of the management of Encana as to Newfields
and Encanas existing technology and future capabilities with respect to the extraction of Newfields and Encanas oil and gas reserves and other oil and gas resources and associated timing and costs and, with Encanas consent,
assumed that there had been no developments that would adversely affect such managements views with respect to such technologies, capabilities, timing and costs. Credit Suisse also assumed, with Encanas consent, that, in the course of
obtaining any regulatory or third party consents, approvals or agreements in connection with the merger, no delay, limitation, restriction or condition would be imposed that would have an adverse effect on Newfield, Encana or the contemplated
benefits of the merger, that the merger would be consummated in accordance with all applicable laws and regulations, and that the merger would be consummated in accordance with the terms of the merger agreement, without waiver, modification or
amendment of any term, condition or agreement thereof material to Credit Suisses analyses or opinion. In addition, Credit Suisse was not requested to, and did not, make an independent evaluation or appraisal of the assets or liabilities
(contingent or otherwise) of Newfield or Encana, and Credit Suisse was not furnished with any such evaluations or appraisals (other than oil and gas reserve information, including the Newfield Reserve Information and the Encana Reserve Information).
With Encanas consent, Credit Suisse assumed that the final form of the merger agreement, when executed by the parties thereto, would conform to the draft reviewed by it in all respects material to its analyses and opinion.

Credit Suisses opinion addressed only the fairness, from a financial point of view, to Encana of the exchange ratio in the merger
pursuant to the merger agreement and did not address any other aspect or implication (financial or otherwise) of the merger or any agreement, arrangement or understanding entered into in connection therewith or otherwise, including, without
limitation, the fairness of the amount or nature of, or any other aspect relating to, any compensation or consideration to be received or otherwise payable to any officers, directors, employees, securityholders or affiliates of any party to the
merger, or class of such persons, relative to the exchange ratio or otherwise. Furthermore, Credit Suisse did not express any advice or opinion regarding matters that require legal, regulatory, accounting, insurance, tax, environmental, executive
compensation or other similar professional advice, including, without limitation, any advice regarding the amounts of any companys oil and gas reserves, the riskings of such reserves or any other aspects of any companys (including
Newfields or Encanas) oil and gas reserves. Credit Suisse assumed that Encana had or would obtain such advice or opinions from the appropriate professional sources. The issuance of Credit Suisses opinion was approved by its
authorized internal committee.

Credit Suisses opinion was necessarily based upon information made available to Credit Suisse as of
the date of its opinion and financial, economic, market and other conditions as they existed and could be evaluated

90

on the date of its opinion. Credit Suisse did not undertake, and is under no obligation, to update, revise, reaffirm or withdraw its opinion, or otherwise comment on or consider events occurring
or coming to its attention after the date of its opinion. In addition, as Encana was aware, the financial projections and estimates that Credit Suisse reviewed relating to the future financial performance of Newfield and Encana reflected certain
assumptions regarding the oil and gas industry and future commodity prices associated with that industry that were subject to significant uncertainty and volatility and that, if different than assumed, could have a material impact on Credit
Suisses analyses and opinion. Also, as Encana was aware, the credit, financial and stock markets had been experiencing unusual volatility and Credit Suisse expressed no opinion or view as to any potential effects of such volatility on
Newfield, Encana or the merger. Credit Suisses opinion did not address the relative merits of the merger as compared to alternative transactions or strategies that might have been available to Encana, nor did it address the underlying business
decision of the Encana board or Encana to proceed with or effect the merger. Credit Suisse did not express any opinion as to what the value of Encana common shares actually would be when issued pursuant to the merger or the price or range of prices
at which Newfield common stock or Encana common shares may be purchased or sold at any time.

In preparing its opinion to the Encana
board, Credit Suisse performed a variety of analyses, including those described below. The summary of Credit Suisses financial analyses is not a complete description of the analyses underlying Credit Suisses opinion. The preparation of
such an opinion is a complex process involving various quantitative and qualitative judgments and determinations with respect to the financial, comparative and other analytic methods employed and the adaptation and application of those methods to
the unique facts and circumstances presented. As a consequence, neither Credit Suisses opinion nor the analyses underlying its opinion are readily susceptible to partial analysis or summary description. Credit Suisse arrived at its opinion
based on the results of all analyses undertaken by it and assessed as a whole and did not draw, in isolation, conclusions from or with regard to any individual analysis, analytic method or factor. Accordingly, Credit Suisse believes that its
analyses must be considered as a whole and that selecting portions of its analyses, analytic methods and factors, without considering all analyses and factors or the narrative description of the analyses, could create a misleading or incomplete view
of the processes underlying its analyses and opinion.

In performing its analyses, Credit Suisse considered business, economic, industry
and market conditions, financial and otherwise, and other matters as they existed on, and could be evaluated as of, the date of its opinion. No company, business or transaction used in Credit Suisses analyses for comparative purposes is
identical to Encana, Newfield or the proposed merger. While the results of each analysis were taken into account in reaching its overall conclusion with respect to fairness to Encana of the exchange ratio in the merger, Credit Suisse did not make
separate or quantifiable judgments regarding individual analyses. The reference ranges indicated by Credit Suisses financial analyses are illustrative and not necessarily indicative of actual values nor predictive of future results or values,
which may be significantly more or less favorable than those suggested by the analyses. In addition, any analyses relating to the value of assets, businesses or securities do not purport to be appraisals or to reflect the prices at which businesses
or securities actually may be sold, which may depend on a variety of factors, many of which are beyond Encanas control and the control of Credit Suisse. Much of the information used in, and accordingly the results of, Credit Suisses
analyses are inherently subject to substantial uncertainty.

Credit Suisses opinion and analyses were provided to the Encana board
(in its capacity as such) in connection with its consideration of the proposed merger and were among many factors considered by the Encana board in evaluating the proposed merger. Neither Credit Suisses opinion nor its analyses were
determinative of the exchange ratio or of the views of the Encana board with respect to the proposed merger. Under the terms of its engagement by Encana, neither Credit Suisses opinion nor any other advice or services rendered by it in
connection with the proposed merger or otherwise, should be construed as creating, and Credit Suisse should not be deemed to have, any fiduciary duty to the Encana board, Encana, Newfield, any securityholder or creditor of Encana or Newfield or any
other person, regardless of any prior or ongoing advice or relationships.

The following is a summary of certain financial analyses
reviewed by Credit Suisse with the Encana board in connection with the rendering of its opinion to the Encana board on October 31, 2018. The summary does not

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contain all of the financial data securityholders of Encana may want or need for purposes of making an independent determination of fair value. Securityholders of Encana are encouraged to consult
their own financial and other advisors before making any investment decision in connection with the proposed merger. The analyses summarized below include information presented in tabular format. The tables alone do not constitute a complete
description of the analyses. Considering the data in the tables below without considering the full narrative description of the analysesas well as the methodologies underlying, and the assumptions, qualifications and limitations affecting,
each analysiscould create a misleading or incomplete view of Credit Suisses analyses.

For purposes of its analyses, Credit
Suisse reviewed a number of financial metrics including:



Enterprise Valuegenerally the value as of a specified date of the relevant companys
outstanding equity securities (taking into account its options and other outstanding convertible securities) plus the value as of such date of its net debt (the value of its outstanding indebtedness, preferred stock and capital lease obligations
less the amount of cash on its balance sheet).



EBITDAgenerally the amount of the relevant companys earnings before interest, taxes,
depreciation and amortization for a specified time period.

Unless the context indicates otherwise, (1) share
prices for the selected companies used in the selected companies analysis described below were as of October 30, 2018, (2) the transaction values for the selected transactions analysis described below were calculated on an enterprise value
basis based on the consideration proposed to be paid in the selected transactions as of the date of announcement, (3) as authorized by Encana, estimates of future financial performance of Newfield used in the discounted cash flow analysis
described below were based on the Encana Projections for Newfield (reflecting Encana Riskings for Newfield and using NYMEX oil and gas strip pricing as of October 30, 2018) and (4) as authorized by Encana, estimates of future financial
performance of Encana used in the discounted cash flow analysis described below were based on the Encana Projections for Encana (reflecting Encana Riskings for Encana and using NYMEX oil and gas strip pricing as of October 30, 2018). Estimates
of future financial performance for the selected companies for the years ending December 31, 2019 and 2020 listed below under the selected companies analysis used to select the implied multiple ranges were based on publicly available research
analyst estimates for those companies. Credit Suisse was authorized by Encana to rely for its selected companies analyses upon the Encana Projections for Newfield and Encana Projections for Encana for estimates of future financial performance on an
unrisked basis for the years ending December 31, 2019 and 2020 using consensus estimates of research analysts for oil and gas pricing as of October 30, 2018.

Selected Companies Analyses

Credit
Suisse considered certain financial data for Newfield, Encana and selected companies with publicly traded equity securities Credit Suisse deemed relevant. The selected companies were selected because they were deemed to be similar to Newfield and
Encana in one or more respects.

The financial data reviewed included:



Enterprise Value as a multiple of estimated EBITDA for the year ended December 31, 2019, or 2019E
EBITDA;



Enterprise Value as a multiple of estimated EBITDA for the year ended December 31, 2020, or 2020E
EBITDA;



Enterprise Value as a multiple of estimated daily production on a thousand barrels of oil equivalent per day, or
Mboe, basis for the year ended December 31, 2019, or 2019E Daily Production; and



Enterprise Value as a multiple of estimated daily production on an Mboe basis for the year ended
December 31, 2020, or 2020E Daily Production.

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Newfield. The selected companies (with respect to Newfield) and corresponding
financial data based on publicly available research analyst estimates were:

Enterprise value

EBITDA

Daily Production($/Mboe/day)

Company Name

2019E

2020E

2019E

2020E

Continental Resources, Inc.

5.7x

5.1x

$

74,446

$

64,559

Devon Energy Corp.

5.1x

4.3x

34,258

32,557

Noble Energy, Inc.

5.4x

4.0x

43,584

35,267

Marathon Oil Corporation

4.6x

4.3x

45,974

42,370

Cimarex Energy Co.

4.8x

4.0x

35,386

30,911

WPX Energy Inc.

5.0x

4.2x

45,184

47,751

Oasis Petroleum Inc.

4.3x

3.8x

53,241

45,616

Newfield. Taking into account the results of the selected companies analysis, Credit Suisse applied
multiple ranges of 3.5x to 4.5x to Newfields 2019E EBITDA based on the Encana Projections for Newfield (on an unrisked basis and using consensus estimates of research analysts for oil and gas pricing as of October 30, 2018), 3.0x to 4.0x
to Newfields 2020E EBITDA based on the Encana Projections for Newfield (on an unrisked basis and using consensus estimates of research analysts for oil and gas pricing as of October 30, 2018), $30,000 to $40,000 per Mboe/day to
Newfields estimated daily production for 2019, and $27,500 to $37,500 per Mboe/day to Newfields estimated daily production for 2020. The selected companies analysis indicated an implied reference range of $19.16 to $30.15 per share of
Newfield common stock.

Encana. The selected companies (with respect to Encana) and corresponding financial data based on publicly
available research analyst estimates were:

Enterprise Value

EBITDA

Daily Production($/Mboe/day)

Company Name

2019E

2020E

2019E

2020E

EOG Resources, Inc.

6.6x

5.8x

$

80,768

$

68,929

Continental Resources, Inc.

5.7x

5.1x

74,446

64,559

Marathon Oil Corporation

4.6x

4.3x

45,974

42,370

Noble Energy, Inc.

5.4x

4.0x

43,584

35,267

Devon Energy Corp.

5.1x

4.3x

34,258

32,557

WPX Energy Inc.

5.0x

4.2x

45,184

47,751

Cimarex Energy Co.

4.8x

4.0x

35,386

30,911

Seven Generations Energy Ltd.

3.6x

3.4x

24,640

23,105

Tourmaline Oil Corp.

4.7x

3.8x

18,142

16,834

ARC Resources Ltd.

6.0x

4.7x

27,340

24,765

Encana. Taking into account the results of the selected companies analysis, Credit Suisse applied
multiple ranges of 4.0x to 5.0x to the Encanas 2019E EBITDA based on the Encana Projections for Encana (on an unrisked basis and using consensus estimates of research analysts for oil and gas pricing as of October 30, 2018), 3.5x to 4.5x
to Encanas 2020E EBITDA based on the Encana Projections for Encana (on an unrisked basis and using consensus estimates of research analysts for oil and gas pricing as of October 30, 2018), $30,000 to $40,000 per Mboe/day to Encanas
estimated daily production for 2019, and $30,000 to $40,000 per Mboe/day to Encanas estimated daily production for 2020. The selected companies analysis indicated an implied reference range of $9.71 to $13.90 per Encana common share.

The selected companies analysis indicated an implied exchange ratio reference range of 1.3783 to 3.1061 Encana common shares for each share of
Newfield common stock, as compared to the exchange ratio in the merger of 2.6719 Encana common shares for each share of Newfield common stock.

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Discounted Cash Flow Analysis

Newfield. Credit Suisse performed a discounted cash flow analysis of Newfield by calculating the estimated net present value of the
projected after-tax, unlevered, free cash flows of Newfield based on the Encana Projections for Newfield and the Encana Riskings for Newfield. At the direction of Encanas management, Credit Suisse
applied NYMEX oil and gas strip pricing as of October 30, 2018, with prices held flat after 2023. Credit Suisse applied discount rates ranging from 8.0% to 10.0% to the projected unlevered free cash flows. The discounted cash flow analysis for
Newfield indicated implied reference ranges per share of Newfield common stock of $27.60 to $37.14.

Encana. Credit Suisse
performed a discounted cash flow analysis of Encana by calculating the estimated net present value of the projected after-tax, unlevered, free cash flows of Encana based on the Encana Projections for Encana
and the Encana Riskings for Encana. At the direction of Encanas management, Credit Suisse applied NYMEX oil and gas strip pricing as of October 30, 2018, with prices held flat after 2023. Credit Suisse applied discount rates ranging from
8.0% to 10.0% to the projected unlevered free cash flows. The discounted cash flow analysis for Encana indicated implied reference ranges per Encana common share of $11.40 to $14.94.

The discounted cash flow analysis indicated implied exchange ratio reference ranges of 1.8478 to 3.2582 Encana common shares for each share of
Newfield common stock, as compared to the exchange ratio in the merger of 2.6719 Encana common shares for each share of Newfield common stock.

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Selected Transactions Analysis

Credit Suisse also considered the financial terms of certain business combinations and other transactions that Credit Suisse deemed relevant.
The selected transactions were selected because the target companies or assets were deemed by Credit Suisse to be similar to Newfield in one or more respects. The financial data reviewed included the implied Transaction Value as a multiple of EBITDA
for the latest twelve months (LTM EBITDA).

Date

Announced

Acquirer

Target

Transaction Value /LTM EBITDA

08/18

Diamondback Energy Inc.

Energen Corporation

10.3x

03/18

Concho Resources Inc.

RSP Permian Inc.

16.2x

06/17

EQT Corporation

Rice Energy Inc.

11.0x

05/15

Noble Energy, Inc.

Rosetta Resources Inc.

6.1x

12/14

Repsol SA

Talisman Energy

5.1x

09/14

Encana Corp

Athlon Energy Inc.

25.1x

07/14

Whiting Petroleum Corp.

Kodiak Oil & Gas Corp.

7.7x

03/14

Energy XXI Ltd.

EPL Oil & Gas, Inc.

4.8x

02/14

Baytex Energy Corp.

Aurora Oil & Gas Limited

NA

11/13

Linn Energy / LinnCo

Berry Petroleum Company

7.4x

12/12

Freeport-McMoRan Copper &Gold Inc.

Plains Exploration & ProductionCompany

5.3x

07/12

CNOOC

Nexen Inc.

4.1x

06/12

PETRONAS

Progress Energy Resources Corp.

25.0x

01/12

Denver Parent Corporation

Venoco, Inc.

6.9x

10/11

Sinopec International Petroleum

and Production Corp

Daylight Energy Ltd.

9.4x

07/11

CNOOC

OPTI Canada Inc.

N/A

07/11

BHP Billiton

Petrohawk Energy Corporation

12.4x

11/10

Chevron Corporation

Atlas Energy, Inc.

19.2x

04/10

Sandridge Energy Inc.

Arena Resources Inc.

9.9x

03/10

CONSOL Energy Inc.

CNX Gas Corporation

15.5x

12/09

Exxon Mobil Corp.

XTO Energy Inc.

6.0x

11/09

Denbury Resources Inc.

Encore Acquisition Company

11.8x

03/09

Suncor Energy Inc.

Petro-Canada

2.2x

07/08

Royal Dutch Shell plc

Duvernay Oil Corp.

18.8x

10/07

Penn West Energy Trust

Canetic Resources Trust

7.0x

07/07

Marathon Oil

Western Oil Sands, Inc.

15.4x

07/07

Plains Exploration & ProductionCompany

Pogo Producing Co.

7.1x

01/07

Forest Oil Corporation

Houston Exploration Company

4.6x

06/06

Anadarko Petroleum Corporation

Western Gas Resources, Inc.

10.2x

04/06

Petrohawk Energy Corporation

KCS Energy Inc.

5.7x

12/05

ConocoPhillips

Burlington Resources Inc.

6.3x

10/05

Occidental Petroleum Corporation

Vintage Petroleum, Inc.

7.5x

04/05

Chevron Corp.

Unocal Corp.

5.1x

01/05

Cimarex Energy Co.

Magnum Hunter Resources Inc.

6.6x

Taking into account the results of the selected transactions analysis, Credit Suisse applied a multiple range
of 6.0x to 8.0x to Newfields LTM EBITDA (as of September 30, 2018). The selected transactions analysis indicated an implied reference range per share of Newfield common stock of $30.15 to $44.79. The selected transactions analysis for
Newfield and the selected companies analysis for Encana indicated an implied exchange ratio reference Encana of 2.1680 to 4.6147 Encana common shares for each share of Newfield common stock as

95

compared to the exchange ratio in the merger of 2.6719 Encana common shares for each share of Newfield common stock.

Other Information

Credit Suisse also
reviewed with the Encana board financial information and analyses relating to the potential cost savings anticipated by Encanas management to result from the merger.

Other Matters

Encana retained Credit
Suisse as its financial advisor in connection with the merger based on Credit Suisses qualifications, experience and reputation as an internationally recognized investment banking and financial advisory firm. Pursuant to the engagement letter
between Encana and Credit Suisse, Encana has agreed to pay Credit Suisse a fee of $22 million for its services of which $3.5 million became payable to Credit Suisse upon the rendering of its opinion to the Encana board and the remainder of
which is contingent upon the consummation of the merger. In addition, Encana has agreed to reimburse certain of Credit Suisses expenses and to indemnify Credit Suisse and certain related parties for certain liabilities and other items arising
out of or related to its engagement.

Credit Suisse and its affiliates have in the past provided and currently are providing investment
banking and other financial advice and services to Encana and its affiliates for which advice and services Credit Suisse and its affiliates have received and would expect to receive compensation, including among other things, during the past two
years, having been and continuing to be a lender to Encana and having acted as a lead underwriter in connection with the public offering of securities by Encana in September 2016. Credit Suisse and its affiliates have in the past provided and
currently are providing investment banking and other financial advice and services to Newfield and its affiliates for which advice and services Credit Suisse and its affiliates have received and would expect to receive compensation, including among
other things, during the past two years, having been and continuing to be a lender to Newfield and having acted as a lead underwriter in connection with the public offering of securities by Newfield in February 2016. Credit Suisse and its affiliates
may in the future provide investment banking and other financial advice and services to Encana, Newfield and their respective affiliates for which advice and services Credit Suisse and its affiliates would expect to receive compensation. Since
January 1, 2016, Credit Suisse received approximately $9 million in fees for investment banking services from Newfield and its affiliates in matters unrelated to the merger and approximately $6 million in fees for investment banking
services from Encana and its affiliates in matters unrelated to the merger. Credit Suisse is a full service securities firm engaged in securities trading and brokerage activities as well as providing investment banking and other financial advice and
services. In the ordinary course of business, Credit Suisse and its affiliates may acquire, hold or sell, for its and its affiliates own accounts and the accounts of customers, and equity, debt and other securities and financial instruments
(including bank loans and other obligations) of Encana, Newfield and any other company that may be involved in merger, as well as provide investment banking and other financial advice and services to such companies and their affiliates.

Opinion of TD Securities

The
Encana board retained TD Securities to act as a financial advisor and to render an opinion to the Encana board as to the fairness, from a financial point of view, to Encana, of the exchange ratio pursuant to the merger agreement. On October 31,
2018, TD Securities rendered to the Encana board its oral opinion, which it subsequently confirmed in writing on October 31, 2018, that as of that date and based on and subject to the matters considered, the procedures followed, the assumptions
made and various limitations of, and qualifications to, the review undertaken by TD Securities as set forth in its written opinion, the exchange ratio was fair, from a financial point of view, to Encana.

The full text of the written opinion of TD Securities to the Encana board, dated as of October 31, 2018, is attached as Annex C to
this joint proxy statement/prospectus and is incorporated herein by reference in its

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entirety. The summary of the opinion of TD Securities in this joint proxy statement/prospectus is qualified in its entirety by reference to the full text of the opinion. Encana shareholders
should read TD Securities opinion and this summary of TD Securities opinion carefully and in their entirety for a discussion of the matters considered, the procedures followed, the assumptions made and various limitations of, and
qualifications to, the review undertaken by TD Securities in rendering its opinion.

TD Securities opinion was provided to
the Encana board (in its capacity as such) for its information in connection with its consideration of the merger. TD Securities opinion does not constitute a recommendation to the Encana board with respect to the merger, nor does TD
Securities opinion constitute advice or a recommendation to any Encana shareholder or Newfield stockholder as to how to vote with respect to the merger and does not in any manner address the prices at which Encana common shares will trade at
any time. TD Securities opinion addresses only the fairness, from a financial point of view and as of the date of such opinion, of the exchange ratio pursuant to the merger agreement and does not address any terms or other aspects of the
merger or any other matter.

For purposes of rendering its opinion and performing its related financial analyses, TD Securities:



reviewed the draft merger agreement;



reviewed certain publicly available financial statements and other business and financial information of Encana
and Newfield, respectively;

reviewed estimates of certain oil and gas reserves and resources engineering analyses relating to Encana and
Newfield and prepared by the respective managements of Encana and Newfield and their reserve evaluators (the Engineering Analyses);



discussed the past and current operations and financial condition and the prospects of Encana and Newfield with
senior executives of Encana and Newfield, respectively;



reviewed information relating to certain strategic, financial and operational benefits anticipated from the
merger, with senior executives of Encana, including the amounts and timing of the cost savings and operational synergies expected by the management of Encana to result from a combination of the businesses of Encana and Newfield;



reviewed certain financial projections and operating data prepared by the management of Encana (the Encana
Projections) and by the management of Newfield (the Newfield Projections), including, in each case, certain adjustments thereto prepared at the direction of the management of Encana or otherwise authorized by management of Encana
to be used and relied upon by TD Securities;

reviewed the historical market prices and trading activity for Encana common shares and Newfield common stock and
compared the financial performance of Encana and Newfield and the prices and trading activity of Encana common shares and Newfield common stock with each other and with that of certain other publicly-traded companies considered comparable with
Encana and Newfield, respectively;



reviewed the financial terms, to the extent publicly available, of selected acquisition transactions;



reviewed published estimates of research analysts with respect to Encana and Newfield;



reviewed certain publicly available data regarding future oil and gas commodity prices including certain
extrapolations therefrom prepared at the direction of Encana or otherwise authorized by Encana to be used and relied upon by TD Securities (the Commodity Pricing Data); and

97



performed such other analyses and reviewed such other information and considered such other matters as TD
Securities deemed appropriate.

For purposes of rendering its opinion, TD Securities assumed and relied upon, without
independent verification, the accuracy and completeness of the information that was publicly available or supplied or otherwise made available to, or discussed with, TD Securities, by Encana and Newfield. With respect to the Encana Projections and
the Newfield Projections, including certain adjustments thereto prepared at the direction of the management of Encana or otherwise authorized by the management of Encana to be used and relied upon by TD Securities, TD Securities was advised by the
management of Encana, and assumed, that such projections were reasonably prepared on bases reflecting the best currently available estimates and judgments of the respective managements of Encana and Newfield of the future financial performance of
Encana and Newfield, respectively. With respect to the Expected Synergies, TD Securities was advised by the management of Encana, and assumed, that such Expected Synergies were reasonably prepared on bases reflecting the best currently available
estimates and judgments of the management of Encana and assumed that such Expected Synergies would be realized in the amounts and the times indicated thereby. With respect to the Engineering Analyses, TD Securities was advised by the management of
Encana, and assumed, that such reports were reasonably prepared in good faith on bases reflecting the best currently available estimates and judgments as to Encanas and Newfields proved and probable oil and gas reserves. TD Securities
expressed no view or opinion with respect to the Engineering Analyses, the Encana Projections, the Newfield Projections, the Expected Synergies, the Commodity Pricing Data or the assumptions upon which they were based, and, at the direction of
management of Encana, assumed that the Engineering Analyses, the Encana Projections (including certain adjustments thereto prepared at the direction of the management of Encana or otherwise authorized by the management of Encana to be used and
relied upon by TD Securities), the Newfield Projections (including certain adjustments thereto prepared at the direction of the management of Encana or otherwise authorized by the management of Encana to be used and relied upon by TD Securities),
the Expected Synergies and the Commodity Pricing Data, as well as the assumptions upon which they are based, were a reasonable basis on which to evaluate Newfield, Encana and the merger and TD Securities used and relied upon such information for
purposes of its analyses and its opinion.

In arriving at its opinion, TD Securities assumed that the merger would be consummated in
accordance with the terms set forth in the merger agreement, without any waiver, modification or amendment of any material term, condition or agreement, or delay, including, among other things, that the definitive merger agreement would not differ
in any material respect from the draft thereof furnished to TD Securities. In addition, TD Securities assumed that in connection with the receipt of all the necessary governmental, regulatory and third party approvals relating to the proposed
merger, no delays, limitations, conditions, modifications or restrictions would be imposed that could have an adverse effect on Encana, Newfield or the contemplated benefits expected to be derived in the proposed merger.

TD Securities did not make any independent evaluation or appraisal of the assets or liabilities (contingent or otherwise) of Encana or
Newfield, nor was TD Securities furnished with any such evaluation or appraisal, other than the Engineering Analyses, upon which TD Securities relied without independent verification. TD Securities expressed no opinion with respect to the fairness
of the amount or nature of the compensation to any of Newfields officers, directors or employees or any class of such persons, relative to the consideration to be paid to the Newfield stockholders in the transaction. TD Securities relied,
without independent verification, upon the assessments of the management of Encana as to (i) the existing and future technology and products of Newfield and the risks associated with such technology and products, (ii) their ability to
integrate the businesses of Encana and Newfield and (iii) their ability to retain key employees of Encana and Newfield. Additionally, TD Securities are financial advisors only and relied upon, without independent verification, the assessment of
Newfield and its legal, tax, regulatory, accounting, insurance, environmental or other similar professional advisors with respect to legal, tax, regulatory, accounting, insurance, environmental and oil and gas reserve and resource matters.

98

Financial Analyses of TD Securities

The following is a summary of the material financial analyses performed by TD Securities in connection with the delivery to the Encana board of
its oral opinion and its written opinion to the Encana board, each dated as of October 31, 2018. The following summary does not purport to be a complete description of the financial analyses performed by TD Securities, nor does the order of
analyses described represent relative importance or weight given to those analyses by TD Securities. Some of these summaries of the financial analyses include information presented in tabular format. In order to fully understand the financial
analyses used by TD Securities, the tables must be read together with the full text of each summary. The tables alone do not constitute a complete description of TD Securities financial analyses. Except as otherwise noted, the following
quantitative information, to the extent that it is based on market data, is based on market data as it existed on or before October 29, 2018 (which was the last trading day prior to finalization of TD Securities financial analyses), and
is not necessarily indicative of current market conditions.

For purposes of the financial analyses summarized below, the term
implied equity value per share refers to the implied equity value per share for Newfield common stock of $26.47 (rounded down to the nearest cent) based on the exchange ratio of 2.6719 pursuant to the merger agreement and Encanas
closing share price of $9.91 on October 29, 2018, which was the last trading day prior to finalization of TD Securities financial analyses.

TD Securities performed a NAV analysis on Newfield based on the Newfield Projections, as adjusted at the direction or authorization of the
management of Encana, to estimate the present value of the future after-tax cash flows expected to be generated by the currently producing assets, as well as the total proved and unproved reserves of Newfield.
The projected future unlevered free cash flows for Newfield were based on forecasts for production, cash flows, capital and operating costs provided by Newfield management. TD Securities calculated projected future unlevered after-tax free cash flows using a corporate tax rate of 21% taking into account available tax offsets.

At the direction of the management of Encana, TD Securities calculated NAVs for Newfield using publicly-available strip pricing (as of
October 16, 2018) based on NYMEX commodity prices. The NYMEX commodity prices were used until 2024, after which TD Securities assumed 2.0% escalation annually thereafter.

TD Securities discounted the unlevered after tax cash flows of Newfield to October 1, 2018 for each basin of Newfield using a discount
rate ranging between 8.5% to 9.5%, which was the TD Securities then current estimate of the Newfield weighted average cost of capital (WACC). The resulting present values for each of the Newfield basins were risk-adjusted based on risk
adjusting provided to TD Securities by the management of Encana, which ranged from 0% to 95% of unrisked value.

TD Securities then
subtracted from the aggregate NAVs for all basins of Newfield the present value of Newfields corporate and other expenses using a discount rate ranging between 8.5% to 9.5%, which was TD Securities then current estimate of
Newfields WACC. TD Securities then calculated an illustrative equity value of Newfield by subtracting the book value of Newfields net debt as of September 30, 2018, Newfields net working capital as of September 30,
2018 and asset retirement obligations as of September 30, 2018 and adding the book value of Newfields other assets and liabilities.

TD Securities noted that the analyses implied an equity value per share of Newfield common stock of $38.13 per share to $44.31 per share. TD
Securities noted that the implied equity value per share of Newfield

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common stock based on the exchange ratio pursuant to the merger agreement was $26.47 (rounded down to the nearest cent) and the closing stock price for Newfield common stock on October 29,
2018 was $19.10.

For informational purposes, TD Securities also calculated NAVs for Newfield, without consideration given to the effects
of inflation using publicly-available strip pricing based on NYMEX commodity prices. The NYMEX commodity prices were used until 2024, after which TD Securities held the commodity prices constant through the remainder of the forecast period. TD
Securities then performed the same analyses as above, which resulted in an implied an equity value per share of Newfield common stock of $33.12 per share to $38.18 per share. TD Securities noted that the implied equity value per share of Newfield
common stock based on the exchange ratio pursuant to the merger agreement was $26.47 (rounded down to the nearest cent) and the closing stock price for Newfield common stock on October 29, 2018 was $19.10.

Selected Precedent Transaction Analysis

TD Securities performed a precedent transactions analysis, which is designed to imply a value of a company based on publicly available
financial terms for selected transactions. In connection with its analysis, TD Securities compared publicly available statistics for transactions involving exploration and production (E&P) targets that TD Securities, in the exercise
of its professional judgment, determined to be the most relevant. TD Securities chose such transactions based on, among other things, the similarity of the applicable target companies in the transactions to each of Encanas and Newfields
E&P business with respect to the size, focus, commodity mix, reserve profile, margins and other characteristics of their businesses. The transactions included those announced since January 1, 2013 with upstream values greater than
$1.0 billion that were structured as corporate acquisitions or mergers and where the targets assets were primarily onshore in the continental United States. The following table sets forth the transactions used in such analysis:

Date

Announced

Acquirer

Target

08/18

Diamondback Energy, Inc.

Energen Corporation

08/18

Diamondback Energy, Inc.

Ajax Resources, LLC

07/18

BP Plc

BHP Billiton / Petrohawk Energy

03/18

Concho Resources Inc.

RSP Permian, Inc.

08/17

Silver Run Acquisition Corp. II

Alta Mesa Holdings LP

06/17

EQT Corporation

Rice Energy Inc.

02/17

Parsley Energy, Inc.

Double Eagle Energy Permian LLC

01/17

ExxonMobil Corporation

Bass Companies (BOPCO)

01/17

Noble Energy, Inc.

Clayton Williams Energy, Inc.

12/16

Diamondback Energy, Inc.

Brigham Resources Operating, LLC

12/16

Gulfport Energy Corporation

Vitruvian II Woodford, LLC

10/16

SM Energy Company

QStar LLC; RRP

10/16

RSP Permian Inc.

Silver Hill Energy Partners LLC

09/16

Rice Energy Inc.

Vantage Energy, LLC

09/16

EOG Resources Inc.

Yates Petroleum Corp.

07/16

Silver Run Acquisition Corporation

Centennial Resource Production, LLC

05/16

Range Resources Corporation

Memorial Resource Development Corp.

12/15

Devon Energy Corp.

Felix Energy LLC

07/15

WPX Energy Inc.

RKI Exploration & Production LLC

05/15

Noble Energy, Inc.

Rosetta Resources Inc.

09/14

Encana Corp.

Athlon Energy Inc.

07/14

Breitburn Energy Partners LP

QR Energy, LP

07/14

Whiting Petroleum Corporation

Kodiak Oil & Gas Corp.

05/14

Sabine Oil & Gas Corp.

Forest Oil Corp.

02/14

Baytex Energy Corp.

Aurora Oil & Gas Ltd.

02/13

Linn Energy Inc.

Berry Petroleum Company

100

No transaction utilized in the precedent transaction analysis is identical to Encana,
Newfield or the merger. In evaluating the precedent transactions, TD Securities therefore made qualitative judgments and assumptions with regard to general business, market and financial conditions and other matters, which are beyond the control of
Encana and Newfield. These include, among other things, the impact of competition on the business of Newfield or the industry generally, industry growth, commodity prices and the absence of any adverse material change in the financial condition of
Newfield or the industry or in the financial markets in general, which could affect the public trading value of the companies and the aggregate value and equity value of the transactions to which they are being compared. TD Securities also used its
professional judgment concerning differences between the characteristics of the selected precedent transactions and the merger.

Based on
publicly available financial data including company filings, TD Securities analyzed for the precedent transactions the ratio of enterprise value (calculated as market capitalization plus net debt and preferred stock) to (i) last twelve months
(LTM) of earnings before interest, taxes, depreciation and amortization (EBITDA) for the applicable target company prior to the transaction, (ii) the then current production for each target and (iii) the then proved
reserves for each target. Based on this analysis and its professional judgment, TD Securities selected ranges of enterprise value to LTM EBITDA, enterprise value to current production and enterprise value to proved reserves and applied these ranges
to the applicable statistic for Newfield in order to derive a range of implied equity value per share of Newfield common stock. The analyses indicated the following: